| Diagnosis and Testing Refer to Wiring Diagrams Section 412-00, for schematic and connector information. Special Tool(s) | | Terminal probe kit 418-S035 | General Equipment Digital Multimeter (compatible with K-type thermocouple) Thermometer - Fluke 80 PK-8 (FSE number 260 4102 001 07) Worldwide Diagnostic System (WDS) Refrigerant center Vacuum pump. Vacuum gauge Inspection and Testing - Visually CHECK for any obvious mechanical or electrical damage.
Visual Inspection | Mechanical | Electrical | - Refrigerant lines
- Condenser
- Drive belt
- Coolant level
- Coolant hoses
- A/C compressor
- Vacuum lines
| - Fuses
- Wiring harness
- Connector
| - RECTIFY any obvious causes for a concern found during the visual inspection before performing any further tests. CHECK the operation of the system.
- If the concern persists after the visual inspection, PERFORM a fault diagnosis on the electronic engine management with WDS and RECTIFY any displayed faults in accordance with the displayed fault description. CHECK the operation of the system.
- For vehicles with no stored fault(s), PROCEED in accordance with the Symptom Chart according to the fault symptom.
- Following checking or elimination of the fault and after completion of operations, the fault memories of all vehicle modules must be READ OUT and any stored faults must be DELETED. READ OUT all fault memories again following a road test.
Refrigerant Circuit - Quick Check WARNING:The air conditioning system is filled with R134a refrigerant. Observe "Health and Safety Precautions". For further information
REFER to: Gesundheits- und Sicherheitsvorkehrungen (100-00 Allgemeine Informationen, Description and Operation).
Refrigerant circuit check WARNING:Under certain circumstances, refrigerant lines and A/C components may be extremely hot or cold. Exercising care, touch the refrigerant lines or A/C components in order to check this. Failure to observe this instruction can lead to injury. - The refrigerant line from the refrigerant compressor to the condenser must be hot.
- The refrigerant line from the A/C condenser to the fixed orifice tube must be warm, but not so hot as the refrigerant line mentioned above.
- Determine the difference in temperature upstream and downstream of the A/C condenser by measuring the temperatures. Depending on the ambient temperature, the temperature difference should be more than 20 °C. If the temperature difference is less, check the condenser for contamination or damage to the fins as well as operation of the radiator fans.
- The refrigerant line between the fixed orifice tube and the evaporator must be cold from the point where the fixed orifice tube is installed. Depending on the weather, the refrigerant line may also have ice on its surface.
- The refrigerant line between the evaporator and the A/C compressor including the dehydrator must be cold.
Evaporator outlet temperature test To test the power of the A/C system, the temperature of the evaporator outlet line must be measured. To do this, the following preconditions must be met: - Open all windows.
- Set the air distribution to the defrost/dashboard position and open all the ventilation nozzles.
- DO NOT switch on recirculated air.
- Select lowest blower switch setting.
- Select lowest temperature setting.
NOTE:The temperature measurement cannot be done with a thermometer which makes no contact. False measurements may arise as a result of surface reflections. Connect the temperature sensor (Fluke 80 PK-8) to the outlet line of the evaporator. The temperature sensor must be positioned as closely as possible to the evaporator. Connect the temperature sensor to the multimeter. Start the engine and allow it to run at idle speed for several minutes. Switch on the air-conditioning system. After three minutes, measure the surface temperature of the evaporator outlet line. If the measured temperature is 5 °C (vehicles with additional air conditioning: 2 °C) or less then the air conditioning system is OK. If the temperature is higher, the A/C system may be under-filled. Frequent faults and their causes If the customer expresses concern about insufficient cooling performance, ensure that the temperature control is working properly. - No or poor cooling performance:
- Blockage or narrowing of a refrigerant line or in the dehydrator: The location of the blockage or narrowing can easily be located by temperature comparisons at the refrigerant lines and the dehydrator. The blockage or restriction is located at the point where the temperature difference is identified. Note: A difference in temperature in the area of the fixed orifice tube is normal. Once you have found the location of the blockage or narrowing, check the corresponding component and replace it with a new one if required. - Sudden drop in cooling performance (after the air conditioning has been switched off for approx. 5 minutes, the cooling performance returns to normal):
- The cause is an iced-up fixed orifice tube because of moisture in the refrigerant circuit. In order to ensure that moisture is completely removed from the refrigerant circuit, the dehydrator should be renewed and the evacuation time should be extended to 2-3 hours. For further information Symptom chart Symptom chart | Symptom | Possible Sources | Action | | Blower faulty/inoperative | * Fuse(s) * Circuit(s) * Blower motor * Blower switch * Blower resistor assembly * Blower relay, programmable fuel-fired booster heater * Blower relay, air conditioning | * | | Additional blower motor faulty / inoperative | * Fuse(s) * Circuit(s) * Additional blower motor * Additional blower switch * Additional blower resistor | * | | Air conditioning inoperative - blower function OK | * Fuse(s) * Circuit(s) * Air conditioning clutch * Air conditioning clutch relay * Refrigerant high pressure switch * Powertrain control module (PCM) * Refrigerant low pressure switch * Air conditioning control assembly | * | | Refrigerant compressor inoperative in "defrost" air distribution setting (function of air conditioning OK) | * Circuit(s) * Mechanical actuation of the defrost switch * Defrost switch | * | | Blower does not run automatically when the air conditioning is switched on - vehicles with air conditioning | * Circuit(s) * Blower relay, air conditioning | * | | Temperature control inoperative - vehicles with air conditioning (function of the air conditioning OK) | * Circuit(s) * Temperature control potentiometer * Temperature control flap actuator * Temperature control flap * Air conditioning control assembly | * | | Air distribution flap actuator for additional heater inoperative (operation of additional blower motor OK) | * Fuse(s) * Circuit(s) * Actuator – additional heater air distribution flap * Additional heater control assembly | * | | The temperature control is inoperative when the additional heater control assembly is used. | * Fuse(s) * Circuit(s) * Additional heater control valve * Additional heater control valve module * Additional heater control assembly | * | | Recirculated air flap inoperative | * Vacuum line(s). * Actuator – recirculated air flap * Climate control system control assembly | * | | No heating power | * Cooling system * Vacuum line(s). * Circuit(s) * Coolant shut-off valve * Solenoid valve, coolant shut-off valve * Solenoid valve switch, coolant shut-off valve | * | System Checks | PINPOINT TEST A : BLOWER FAULTY/INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | A1: CHECK ALL SPEED SETTINGS OF THE BLOWER MOTOR | | | 1 Ignition switch in position II. | | | 2 Switch the blower switch through all speed settings. | | | Is the blower motor inoperative in all the switch positions? Yes No - The blower motor is inoperative in switch position 1 and/or 2: GO to A9. - The blower motor is only inoperative in switch position 3: GO to A8. | | A2: CHECK FUSE F55 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F55 (standard relay box). | | | Is the fuse OK? Yes No INSTALL A NEW fuse F55 (40 A). CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | A3: CHECK THE VOLTAGE AT FUSE F55 | | | 1 Connect Fuse F55 (standard relay box). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F55 and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F55 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A4: CHECK VOLTAGE AT BLOWER MOTOR | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH123 from the blower motor. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the blower motor, connector CH123, pin 1, circuit CB155J (YE/RD), wiring harness side and ground. | | | Does the meter display battery voltage? Yes - All except vehicles with programmable fuel-fired booster heater: GO to A5. - Vehicles with programmable fuel-fired booster heater: GO to A19. No - All except vehicles with programmable fuel-fired booster heater: LOCATE and REPAIR the break in the circuit between the blower motor and fuse F55 using the Wiring Diagrams. CHECK the operation of the system. - Vehicles with programmable fuel-fired booster heater: GO to A14. | | A5: CHECK GROUND CONNECTION OF BLOWER MOTOR | | | 1 Ignition switch in position 0. | | | 2 Set the blower switch to level 3. | | | 3 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower motor. CHECK the operation of the system. No | | A6: CHECK THE GROUND CONNECTION OF THE BLOWER SWITCH | | | 1 Disconnect Connector CH101B from the blower switch. | | | 2 Measure the resistance between the blower switch, connector CH101B, pin 4, circuit GD115F (BK/RD), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in the circuit between the blower switch and ground connection GP15 using the Wiring Diagrams. CHECK the operation of the system. | | A7: CHECK CIRCUIT BETWEEN THE BLOWER MOTOR AND THE BLOWER SWITCH FOR OPEN CIRCUIT | | | 1 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and the blower switch, connector CH101B, pin 2, circuit VH301A (YE/BU), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit VH301B (YE/BU) between the blower motor and soldered connection S2H301 using the Wiring Diagrams. CHECK the operation of the system. | | A8: CHECK THE CIRCUIT BETWEEN THE BLOWER MOTOR AND THE BLOWER SWITCH FOR OPEN CIRCUIT - LEVEL 3 INOPERATIVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH123 from the blower motor. | | | 3 Disconnect Connector CH101B from the blower switch. | | | 4 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and the blower switch, connector CH101B, pin 2, circuit VH301A (YE/BU), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit VH301A (YE/BU) between soldered connection S2H301 and the blower switch using the Wiring Diagrams. CHECK the operation of the system. | | A9: MEASURE THE VOLTAGE AT THE BLOWER RESISTOR ASSEMBLY | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH403 from the blower resistor assembly. | | | 3 Ignition switch in position II. | | | 4 Measure the resistance between the blower resistor assembly, connector CH403, pin 1, circuit VH301C (YE/BU), wiring harness side and ground. | | | Does the meter display battery voltage? Yes INSTALL a new heater blower series resistor. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit VH301C (YE/BU) between soldered connection S2H301 and the blower resistor assembly using the Wiring Diagrams. CHECK the operation of the system. | | A10: CHECK THE GROUND CONNECTION OF BLOWER RESISTOR ASSEMBLY - LEVEL 1 | | | 1 Ignition switch in position 0. | | | 2 Set the blower switch to level 1. | | | 3 Measure the resistance between the blower resistor assembly, connector CH403, pin 2, circuit CH427C (BN), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No | | A11: CHECK THE CIRCUIT BETWEEN THE BLOWER RESISTOR ASSEMBLY AND THE BLOWER SWITCH FOR OPEN CIRCUIT - LEVEL 1 | | | 1 Disconnect Connector CH101B from the blower switch. | | | 2 Measure the resistance between the blower resistor assembly, connector CH403, pin 2, circuit CH427C (BN), wiring harness side and the blower switch, connector CH101B, pin 3, circuit CH427B (BN), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the blower switch and the blower resistor assembly using the Wiring Diagrams. CHECK the operation of the system. | | A12: CHECK THE GROUND CONNECTION OF BLOWER RESISTOR ASSEMBLY - LEVEL 2 | | | 1 Set the blower switch to level 2. | | | 2 Measure the resistance between the blower resistor assembly, connector CH403, pin 4, circuit CH428A (GN/WH), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes INSTALL a new heater blower series resistor. CHECK the operation of the system. No | | A13: CHECK THE CIRCUIT BETWEEN THE BLOWER RESISTOR ASSEMBLY AND THE BLOWER SWITCH FOR OPEN CIRCUIT - LEVEL 2 | | | 1 Disconnect Connector CH101B from the blower switch. | | | 2 Measure the resistance between the blower resistor assembly, connector CH403, pin 4, circuit CH428A (GN/WH), wiring harness side and the blower switch, connector CH101B, pin 1, circuit CH428A (GN/WH), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit CH428A (GN/WH) between the blower switch and the blower resistor assembly using the Wiring Diagrams. CHECK the operation of the system. | | A14: CHECK THE BLOWER MOTOR CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Blower relay for the programmable fuel-fired booster heater from socket CH402A. | | | 3 Use a fused test cable (5 A) to bridge the blower relay of the programmable fuel-fired booster heater, socket CH402A, between pin 4, circuit CB155G (BN/BU), wiring harness side and pin 1, circuit CB155F (BN/BU), wiring harness side. | | | 4 Ignition switch in position II. | | | 5 Measure the voltage between the blower motor, connector CH123, pin 1, circuit CB155A (BN/BU), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No | | A15: CHECK THE VOLTAGE AT THE BLOWER RELAY OF THE PROGRAMMABLE FUEL-FIRED BOOSTER HEATER | | | 1 Measure the voltage between the blower relay of the programmable fuel-fired booster heater, socket CH402A, pin 4, circuit CB154G (VT/OG) (vehicles without air conditioning: circuit CB154C (VT/OG)), wiring harness side and ground. | | | Does the meter display battery voltage? Yes LOCATE and REPAIR the break in the circuit between the blower relay for the programmable fuel-fired booster heater and the blower motor with the aid of the Wiring Diagrams. CHECK the operation of the system. No | | A16: CHECK THE CIRCUIT BETWEEN THE BLOWER RELAY OF THE PROGRAMMABLE FUEL-FIRED BOOSTER HEATER AND THE PROGRAMMABLE FUEL-FIRED BOOSTER HEATER RELAY FOR OPEN CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Relay R16. | | | 3 Measure the resistance between the blower relay of the programmable fuel-fired booster heater, socket CH402A, pin 4, circuit CB154G (VT/OG) (vehicles without air conditioning: circuit CB154C (VT/OG)), wiring harness side and the programmable fuel-fired booster heater relay, pin 5, circuit CB154A (VT/OG), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes CHECK and if necessary RENEW the fuel-fired booster heater relay. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the blower relay for the programmable fuel-fired booster heater and the programmable fuel-fired booster heater relay using the Wiring Diagrams. CHECK the operation of the system. | | A17: CHECK THE VOLTAGE AT THE BLOWER RELAY OF THE PROGRAMMABLE FUEL-FIRED BOOSTER HEATER | | | 1 Measure the voltage between the blower relay of the programmable fuel-fired booster heater, socket CH402A, pin 3, circuit CB150P (YE/OG) (vehicles without air conditioning: circuit CB155G (BN/BU)), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and RECTIFY the break in the circuit between the blower relay of the programmable fuel-fired booster heater and soldered connection S2B150B (vehicles without air conditioning: soldered connection S2B155) using the Wiring Diagrams. CHECK the operation of the system. | | A18: CHECK THE GROUND CONNECTION OF THE BLOWER RELAY FOR THE PROGRAMMABLE FUEL-FIRED BOOSTER HEATER | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the blower relay of the programmable fuel-fired booster heater, socket CH402A, pin 2, circuit GD115P (BK/GY) (vehicles without air conditioning: circuit GD115D (BK/GY)), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower relay for the programmable fuel-fired booster heater CHECK the operation of the system. No LOCATE and RECTIFY the break in circuit GD115P (BK/RD) (vehicles without air conditioning: circuit GD115D (BK/GY)) between the blower relay for the programmable fuel-fired booster heater and ground connection GP15 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A19: CHECK GROUND CONNECTION OF BLOWER MOTOR | | | 1 Set the blower switch to level 3. | | | 2 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the blower motor. CHECK the operation of the system. No - Vehicles with air conditioning: GO to A20. , - Vehicles without air conditioning: GO to A21. | | A20: CHECK BLOWER SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH101B from the blower switch. | | | 3 Set the blower switch to position 3. | | | 4 Measure the resistance at the blower switch, connector CH101B, between pin 2 and pin 4, component side. | | | Is a resistance of less than 2 Ohms registered? Yes No RENEW the blower switch. CHECK the operation of the system. | | A21: CHECK BLOWER SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH426B from the blower switch. | | | 3 Set the blower switch to position 3. | | | 4 Measure the resistance at the blower switch, connector CH426B, between pin 2 and pin 4, component side. | | | Is a resistance of less than 2 Ohms registered? Yes No RENEW the blower switch. CHECK the operation of the system. | | A22: CHECK CIRCUIT BETWEEN THE BLOWER MOTOR AND THE BLOWER SWITCH FOR OPEN CIRCUIT | | | 1 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and the blower switch, connector CH101B, pin 2, circuit VH301A (YE/BU), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit VH301B (YE/BU) between the blower motor and soldered connection S2H301 using the Wiring Diagrams. CHECK the operation of the system. | | A23: CHECK CIRCUIT BETWEEN THE BLOWER MOTOR AND THE BLOWER SWITCH FOR OPEN CIRCUIT | | | 1 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and the blower switch, connector CH426B, pin 2, circuit VH301A (YE/BU), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit VH301B (YE/BU) between the blower motor and soldered connection S2H301 using the Wiring Diagrams. CHECK the operation of the system. | | A24: CHECK CIRCUIT BETWEEN THE BLOWER MOTOR AND THE BLOWER SWITCH FOR OPEN CIRCUIT | | | 1 Measure the resistance between the blower motor, connector CH123, pin 2, circuit VH301B (YE/BU), wiring harness side and the blower switch, connector CH101B, pin 2, circuit VH301A (YE/BU), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit VH301B (YE/BU) between the blower motor and soldered connection S2H301 using the Wiring Diagrams. CHECK the operation of the system. | | A25: CHECK THE CIRCUIT BETWEEN THE BLOWER SWITCH AND THE AIR CONDITIONING BLOWER RELAY FOR OPEN CIRCUIT | | | 1 Disconnect A/C blower relay from socket CH402B. | | | 2 Measure the resistance between the blower switch, connector CH426B, pin 4, circuit GD115A (BK/GY), wiring harness side and the A/C blower relay, socket CH402B, pin 5, circuit GD115A (BK/GY), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115A (BK/GY) between the blower switch and the A/C blower relay with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A26: CHECK THE CIRCUIT BETWEEN THE BLOWER SWITCH AND THE AIR CONDITIONING BLOWER RELAY FOR OPEN CIRCUIT | | | 1 Disconnect A/C blower relay from socket CH402B. | | | 2 Measure the resistance between the blower switch, connector CH101B, pin 4, circuit GD115A (BK/GY), wiring harness side and the A/C blower relay, socket CH402B, pin 4, circuit GD115B (BK/GY), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115A (BK/GY) between the blower switch and the A/C blower relay with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A27: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY | | | 1 Measure the resistance between the A/C blower relay, socket CH405B, pin 1, circuit GD115R (BK/RD), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115R (BK/RD) between the air conditioning blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A28: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY | | | 1 Measure the resistance between the A/C blower relay, socket CH405B, pin 1, circuit GD115U (BK/RD), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115U (BK/RD) between the A/C blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A29: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY | | | 1 Measure the resistance between the A/C blower relay, socket CH402B, pin 2, circuit GD115Q (BK/RD), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115Q (BK/RD) between the air conditioning blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A30: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY | | | 1 Measure the resistance between the A/C blower relay, socket CH402B, pin 2, circuit GD115Q (BK/RD), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115Q (BK/RD) between the air conditioning blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A31: CHECK THE VOLTAGE AT THE AIR CONDITIONING BLOWER RELAY - PIN 1 | | | 1 Ignition switch in position II. | | | 2 Measure the voltage between the A/C blower relay, socket CH402B, pin 1, circuit CB154E (VT/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes RENEW the air conditioning blower relay. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit CB154E (VT/OG) between the A/C blower relay and soldered connection S2B154 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | A32: CHECK THE VOLTAGE AT THE AIR CONDITIONING BLOWER RELAY - PIN 1 | | | 1 Ignition switch in position II. | | | 2 Measure the voltage between the A/C blower relay, socket CH402B, pin 3, circuit CB155E (YE/RD), wiring harness side and ground. | | | Does the meter display battery voltage? Yes RENEW the air conditioning blower relay. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit CB155E (YE/RD) between the air conditioning blower relay and soldered connection S2B155 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST B : ADDITIONAL BLOWER MOTOR FAULTY / INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | B1: CHECK ALL SPEED SETTINGS OF THE ADDITIONAL BLOWER MOTOR | | | 1 Ignition switch in position II. | | | 2 Switch the additional blower motor switch through all settings. | | | Is the additional blower motor inoperative in all the switch positions? Yes No - The additional blower motor is inoperative in switch position 1, 2 and/or 3: GO to B9. - The additional blower motor is only inoperative in switch position 4: GO to B8. | | B2: CHECK FUSE F57 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F57 (standard relay box). | | | Is the fuse OK? Yes No RENEW fuse F57 (30 A). CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | B3: CHECK THE VOLTAGE AT FUSE F57 | | | 1 Connect Fuse F57 (standard relay box). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F57 and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F57 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B4: CHECK THE VOLTAGE AT THE ADDITIONAL BLOWER MOTOR | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH123R from the additional blower motor. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the additional blower motor, connector CH123R, pin 1, circuit CB157D (BN/GN), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in the circuit between the additional blower motor and fuse F57 using the Wiring Diagrams. CHECK the operation of the system. | | B5: CHECK THE GROUND CONNECTION OF THE ADDITIONAL BLOWER MOTOR | | | 1 Ignition switch in position 0. | | | 2 Set the additional blower switch to position 4. | | | 3 Measure the resistance between the additional blower motor, connector CH123R, pin 2, circuit CHA08A (GN/OG), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower motor. CHECK the operation of the system. No | | B6: CHECK THE GROUND CONNECTION OF THE ADDITIONAL BLOWER SWITCH | | | 1 Disconnect Connector CHA05A from the additional blower switch. | | | 2 Measure the resistance between the additional blower switch, connector CHA05A, pin 1, circuit GD149H (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and RECTIFY the break in the circuit between the additional blower switch and ground connection GP49 using the Wiring Diagrams. CHECK the operation of the system. | | B7: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL BLOWER MOTOR AND THE ADDITIONAL BLOWER SWITCH FOR OPEN CIRCUIT | | | 1 Measure the resistance between the additional blower motor, connector CH123R, pin 2, circuit CHA08A (GN/OG), wiring harness side and the additional blower switch, connector CHA05A, pin 6, circuit CHA08F (GN/OG), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the additional blower motor and soldered connection S4HA08 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B8: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL BLOWER MOTOR AND THE ADDITIONAL BLOWER SWITCH FOR OPEN CIRCUIT - LEVEL 4 INOPERATIVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH123R from the additional blower motor. | | | 3 Disconnect Connector CHA05A from the additional blower switch. | | | 4 Measure the resistance between the additional blower motor, connector CH123R, pin 2, circuit CHA08A (GN/OG), wiring harness side and the additional blower switch, connector CHA05A, pin 6, circuit CHA08F (GN/OG), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between soldered connection S4HA08 and the additional blower switch with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B9: CHECK THE VOLTAGE AT THE ADDITIONAL BLOWER RESISTOR | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CHA04 from the additional blower resistor. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the additional blower resistor, connector CHA04, pin 4, circuit CHA08B (GN/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in the circuit between soldered connection S4HA08 and the additional blower resistor with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B10: CHECK THE GROUND CONNECTION OF THE ADDITIONAL BLOWER RESISTOR - LEVEL 1 | | | 1 Ignition switch in position 0. | | | 2 Set the additional blower switch to level 1. | | | 3 Measure the resistance between the additional blower resistor, connector CHA04, pin 3, circuit CHA06D (YE/VT), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No | | B11: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL BLOWER SWITCH AND THE ADDITIONAL BLOWER RESISTOR FOR OPEN CIRCUIT | | | 1 Disconnect Connector CHA05A from the additional blower switch. | | | 2 Measure the resistance between the additional blower switch, connector CHA05A, pin 2, circuit CHA06A (YE/VT), wiring harness side and the additional blower resistor, connector CHA04, pin 3, circuit CHA06D (YE/VT), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the additional blower switch and the additional blower resistor with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B12: CHECK THE GROUND CONNECTION OF THE ADDITIONAL BLOWER RESISTOR - LEVEL 2 | | | 1 Set the additional blower switch to level 2. | | | 2 Measure the resistance between the additional blower resistor, connector CHA04, pin 1, circuit ZA345A (OG/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No | | B13: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL BLOWER SWITCH AND THE ADDITIONAL BLOWER RESISTOR FOR OPEN CIRCUIT | | | 1 Disconnect Connector CHA05A from the additional blower switch. | | | 2 Measure the resistance between the additional blower switch, connector CHA05A, pin 3, circuit ZA345D (OG/GY), wiring harness side and the additional blower resistor, connector CHA04, pin 1, circuit ZA345A (OG/GY), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the additional blower switch and the additional blower resistor with the aid of the Wiring Diagrams. CHECK the operation of the system. | | B14: CHECK THE GROUND CONNECTION OF THE ADDITIONAL BLOWER RESISTOR - LEVEL 3 | | | 1 Set the additional blower switch to level 3. | | | 2 Measure the resistance between the additional blower resistor, connector CHA04, pin 2, circuit CHA07D (BU/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower resistor. CHECK the operation of the system. No | | B15: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL BLOWER SWITCH AND THE ADDITIONAL BLOWER RESISTOR FOR OPEN CIRCUIT | | | 1 Disconnect Connector CHA05A from the additional blower switch. | | | 2 Measure the resistance between the additional blower switch, connector CHA05A, pin 5, circuit CHA07A (BU/GY), wiring harness side and the additional blower resistor, connector CHA04, pin 2, circuit CHA07D (BU/GY), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional blower switch. CHECK the operation of the system. No LOCATE and REPAIR the break in the circuit between the additional blower switch and the additional blower resistor with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST C : AIR CONDITIONING INOPERATIVE - BLOWER FUNCTION OK | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | C1: DETERMINE THE CONDITIONS UNDER WHICH THE FAULT OCCURS | | | 1 Ignition switch in position III. 2 Run the engine at idle speed. | | | 3 Switch on the air-conditioning system. | | | Does the A/C clutch work, and is the A/C indicator lamp on? Yes PERFORM the Refrigerant Circuit Quick Check. No - The A/C indicator lamp is on, but the A/C clutch is not working: GO to C2. - The A/C indicator lamp is not on, but the A/C clutch is working:RENEW the blower switch. CHECK the operation of the system. - The A/C indicator lamp is not on, and the A/C clutch is not working: GO to C21. | | C2: CHECK FUSE F36 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F36 (BJB). | | | Is the fuse OK? Yes No RENEW fuse F36 (10 A). CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | C3: CHECK THE VOLTAGE AT FUSE F36 | | | 1 Connect Fuse F36 (BJB). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F36 (10 A) and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F36 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C4: CHECK FUSE F29 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F29 (BJB). | | | Is the fuse OK? Yes No RENEW fuse F29 (5 A). CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | C5: CHECK THE VOLTAGE AT FUSE F29 | | | 1 Connect Fuse F29 (BJB). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F29 (5 A) and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F29 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C6: CHECK THE CONTROL VOLTAGE AT THE A/C CLUTCH RELAY | | | 1 Ignition switch in position 0. | | | 2 Disconnect A/C clutch relay from socket C1010. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the A/C clutch relay, socket C1010, pin 1, circuit CBB29A (WH/VT), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and RECTIFY the break in circuit CBB29A (WH/VT) between the A/C relay and fuse F29 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C7: CHECK THE VOLTAGE AT THE A/C CLUTCH RELAY | | | 1 Measure the voltage between the A/C clutch relay, socket C1010, pin 3, circuit CBB36A (BU/BN), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and RECTIFY the break in circuit CBB36A (BU/BN) between the A/C relay and fuse F36 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C8: CHECK THE CIRCUIT OF THE A/C CLUTCH | | | 1 Ignition switch in position 0. | | | 2 Using a fused test cable ((10 A), bridge between the relay of the A/C clutch, socket C1010, pin 3, circuit CBB36A (BU/BN), wiring harness side and pin 5, circuit CH109A (WH/OG), wiring harness side. | | | 3 Ignition switch in position II. | | | Does the air conditioning clutch work? Yes No | | C9: CHECK THE VOLTAGE AT THE A/C CLUTCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH302 from the A/C clutch. | | | 3 Using a fused test cable ((10 A), bridge between the relay of the A/C clutch, socket C1010, pin 3, circuit CBB36A (BU/BN), wiring harness side and pin 5, circuit CH109A (WH/OG), wiring harness side. | | | 4 Ignition switch in position II. | | | 5 Measure the voltage between the A/C clutch, connector CH302, pin 1, circuit CH109D (WH/OG) (vehicles with a diesel engine: circuit CH109B (WH/OG)), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the open circuit between the A/C relay and the A/C clutch using the Wiring Diagrams. CHECK the operation of the system. | | C10: CHECK THE GROUND CONNECTION OF THE A/C CLUTCH | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the A/C clutch, connector CH302, pin 2, circuit GD122Q (BK) (vehicles with a diesel engine: circuit GD122G (BK)), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the air conditioning clutch. CHECK the operation of the system. No LOCATE and RECTIFY the break in the circuit between the air conditioning clutch and ground connection GP22 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C11: CHECK AIR CONDITIONING CLUTCH RELAY | | | 1 Check the A/C clutch relay according to the component test at the end of this section. | | | Is the air conditioning clutch relay OK? Yes No RENEW the air conditioning clutch relay. CHECK the operation of the system. | | C12: CHECK THE VOLTAGE AT THE REFRIGERANT HIGH PRESSURE SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH433 from the refrigerant high pressure switch. | | | 3 Ignition switch in position II. | | | 4 Switch on the air-conditioning system. | | | 5 Measure the voltage at the refrigerant high pressure switch, between connector CH433, pin 4, circuit CH421A (GY), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No | | C13: CHECK THE A/C HIGH PRESSURE SWITCH | NOTE:Make sure that the refrigerant pressure is in the range between 3.0 and 10.5 bar (temperature dependent). If the pressure is higher, perform a refrigerant circuit Quick Check. If the pressure is lower, check the refrigerant circuit for leaks. | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance at the refrigerant high pressure switch, connector CH433, between pin 1 and pin 4, component side. | | | Is a resistance of less than 2 Ohms registered? Yes - All except vehicles with diesel engines: GO to C16. No RENEW the refrigerant high pressure switch. CHECK the operation of the system. | | C14: CHECK THE CIRCUIT BETWEEN THE POWERTRAIN CONTROL MODULE (PCM) AND THE REFRIGERANT HIGH PRESSURE SWITCH FOR OPEN CIRCUIT - VEHICLES WITH A DIESEL ENGINE | | | 1 Disconnect Connector CE104B from the PCM. | | | 2 Measure the resistance between the PCM, connector CE104B, pin F2, circuit CH423A (YE), wiring harness side and the refrigerant high pressure switch, connector CH433, pin 1, circuit CH423A (YE), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and RECTIFY the break in circuit CH423A (YE) between the PCM and the refrigerant high pressure switch with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C15: CHECK THE CIRCUIT BETWEEN THE POWERTRAIN CONTROL MODULE (PCM) AND THE A/C CLUTCH RELAY FOR OPEN CIRCUIT - VEHICLES WITH A DIESEL ENGINE | | | 1 Measure the resistance between the PCM, connector CE104B, pin B2, circuit CH401A (VT/WH), wiring harness side and the A/C clutch relay, socket C1010, pin 2, circuit CH401A (VT/WH), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes CHECK the PCM and RENEW if necessary. CHECK the operation of the system. No LOCATE and RECTIFY the break in circuit CH401A (VT/WH) between PCM and the A/C clutch relay with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C16: CHECK THE CIRCUIT BETWEEN THE POWERTRAIN CONTROL MODULE (PCM) AND THE REFRIGERANT HIGH PRESSURE SWITCH FOR OPEN CIRCUIT - ALL VEHICLES EXCEPT VEHICLES WITH A DIESEL ENGINE | | | 1 Disconnect Connector CE512B from the PCM. | | | 2 Measure the resistance between the PCM, connector CE512B, pin F2, circuit CH423A (YE), wiring harness side and the refrigerant high pressure switch, connector CH433, pin 1, circuit CH423A (YE), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and RECTIFY the break in circuit CH423A (YE) between the PCM and the refrigerant high pressure switch with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C17: CHECK THE CIRCUIT BETWEEN THE POWERTRAIN CONTROL MODULE (PCM) AND THE A/C CLUTCH RELAY FOR OPEN CIRCUIT - ALL VEHICLES EXCEPT VEHICLES WITH A DIESEL ENGINE | | | 1 Measure the resistance between the PCM, connector CE512B, pin B2, circuit CH401A (VT/WH), wiring harness side and the A/C clutch relay, socket C1010, pin 2, circuit CH401A (VT/WH), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes CHECK the PCM and RENEW if necessary. CHECK the operation of the system. No LOCATE and RECTIFY the break in circuit CH401A (VT/WH) between PCM and the A/C clutch relay with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C18: CHECK THE VOLTAGE AT THE REFRIGERANT LOW PRESSURE SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH421 from the refrigerant low pressure switch. | | | 3 Ignition switch in position II. | | | 4 Switch on the air-conditioning system. | | | 5 Measure the voltage between the refrigerant low pressure switch, connector CH421, pin 1, circuit CH422A (VT), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No | | C19: CHECK REFRIGERANT LOW PRESSURE SWITCH | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance at the refrigerant low pressure switch, connector CH421, between pin 1 and pin 4, component side. | | | Is a resistance of less than 2 Ohms registered? Yes LOCATE and RECTIFY the break in circuit CH421A (GY) between the refrigerant low pressure switch and the refrigerant high pressure switch with the aid of the Wiring Diagrams. CHECK the operation of the system. No RENEW the refrigerant low pressure switch. CHECK the operation of the system. | | C20: CHECK THE CIRCUIT BETWEEN THE REFRIGERANT LOW PRESSURE SWITCH AND THE A/C CONTROL ASSEMBLY FOR OPEN CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH101C from the A/C control assembly. | | | 3 Measure the resistance between the A/C control assembly, connector CH101C, pin 4, circuit CH422F (VT), wiring harness side and the refrigerant low pressure switch, connector CH421, pin 1, circuit CH422A (VT), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the A/C control assembly. CHECK the operation of the system. No LOCATE and RECTIFY the open circuit between the air conditioning control assembly and the refrigerant low pressure switch with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C21: CHECK THE FUNCTION OF THE DEFROST SWITCH | | | 1 Set the air distribution to defrost. | | | Does the A/C clutch work, and is the A/C indicator lamp on? Yes No | | C22: CHECK FUSE F50 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F50 (standard relay box). | | | Is the fuse OK? Yes No RENEW fuse F50 (10 A). CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | C23: CHECK THE VOLTAGE AT FUSE F50 | | | 1 Connect Fuse F50 (standard relay box). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F50 (10 A) and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F50 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | C24: CHECK THE VOLTAGE AT THE AIR CONDITIONING CONTROL PANEL | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector C101C from the A/C control assembly. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the A/C control assembly, connector C101C, pin 3, circuit CB150N (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes RENEW the A/C control assembly. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit CB150N (YE/OG) between the A/C control assembly and soldered connection S2B150B with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST D : REFRIGERANT COMPRESSOR INOPERATIVE IN "DEFROST" AIR DISTRIBUTION SETTING (FUNCTION OF AIR CONDITIONING OK) | NOTE:Before carrying out the check, make sure that the ambient temperature is above 4°C. | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | D1: MEASURE THE VOLTAGE AT THE DEFROST SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH227 from the defrost switch. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the defrost switch, connector CH227, pin 2, circuit CB150M (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in circuit CB150M (YE/OG) between the defrost switch and soldered connection S2B150B with the aid of the Wiring Diagrams. CHECK the operation of the system. | | D2: CHECK THE CIRCUIT BETWEEN THE DEFROST SWITCH AND THE REFRIGERANT LOW PRESSURE SWITCH FOR OPEN CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH421 from the refrigerant low pressure switch. | | | 3 Measure the resistance between the defrost switch, connector CH227, pin 1, circuit CH422E (VT), wiring harness side and the refrigerant low pressure switch, connector CH421, pin 1, circuit CH422A (VT), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes TEST the mechanical actuation of the defrost switch and REPAIR if necessary. If the mechanical actuation is OK, RENEW the defrost switch. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit CH422E (VT) between the defrost switch and soldered connection S2H422 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST E : BLOWER DOES NOT RUN AUTOMATICALLY WHEN THE AIR CONDITIONING IS SWITCHED ON - VEHICLES WITH AIR CONDITIONING | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | E1: CHECK THE VOLTAGE AT THE AIR CONDITIONING BLOWER RELAY (PIN 3) | | | 1 Ignition switch in position 0. | | | 2 Disconnect A/C blower relay from socket CH402B. | | | 3 Ignition switch in position II. | | | 4 Set the blower switch to position 0. | | | 5 Measure the voltage between the A/C blower relay, socket CH402B, pin 3, circuit CH427D (BN), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in circuit CH427D (BN) between the A/C blower relay and soldered connection S2H427 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | E2: CHECK THE VOLTAGE AT THE AIR CONDITIONING BLOWER RELAY (PIN 1) | | | 1 Switch on the air-conditioning system. | | | 2 Measure the voltage between the A/C blower relay, socket CH402B, pin 1, circuit CH422G (VT), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in circuit CH422G (VT) between the A/C blower relay and soldered connection S2H422 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | E3: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY (PIN 5) | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the air conditioning blower relay, socket CH402B, pin 5, circuit GD115H (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in circuit GD115H (BK/GY) between the A/C blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | E4: CHECK THE GROUND CONNECTION OF THE A/C BLOWER RELAY (PIN 2) | | | 1 Measure the resistance between the A/C blower relay, socket CH402B, pin 2, circuit GD115G (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the air conditioning blower relay. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit GD115G (BK/GY) between the A/C blower relay and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST F : TEMPERATURE CONTROL INOPERATIVE - VEHICLES WITH AIR CONDITIONING (FUNCTION OF THE AIR CONDITIONING OK) | NOTE:Before carrying out the check, make sure that the air distribution flap is mechanically OK. | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | F1: CHECK THE VOLTAGE AT THE TEMPERATURE CONTROL FLAP ACTUATOR | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH232 from the temperature control flap actuator. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the temperature control flap actuator, connector CH232, pin 7, circuit CB150J (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and RECTIFY the open circuit between the temperature control flap actuator and soldered connection S2B150B with the aid of the Wiring Diagrams. CHECK the operation of the system. | | F2: CHECK THE GROUND CONNECTION OF THE TEMPERATURE CONTROL FLAP ACTUATOR | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the temperature control flap actuator, connector CH232, pin 8, circuit GD115D (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and RECTIFY the open circuit between the temperature control flap actuator and soldered connection S2D115C with the aid of the Wiring Diagrams. CHECK the operation of the system. | | F3: CHECK THE CIRCUITS BETWEEN THE TEMPERATURE CONTROL FLAP ACTUATOR AND THE A/C CONTROL ASSEMBLY FOR OPEN CIRCUIT | | | 1 Disconnect Connector CH101D from the A/C control assembly. | | | 2 Measure the resistance between the temperature control flap actuator, connector CH232, pin 4, circuit ZA337A (OG/GY), wiring harness side and the A/C control assembly, connector CH101D, pin 3, circuit ZA337A (OG/GY), wiring harness side. | | | 3 Measure the resistance between the temperature control flap actuator, connector CH232, pin 3, circuit ZA338A (OG/WH), wiring harness side and the A/C control assembly, connector CH101D, pin 2, circuit ZA338A (OG/WH), wiring harness side. | | | 4 Measure the resistance between the temperature control flap actuator, connector CH232, pin 6, circuit ZA339A (OG/BN), wiring harness side and the A/C control assembly, connector CH101D, pin 1, circuit ZA339A (OG/BN), wiring harness side. | | | Is a resistance of less than 2 Ohms measured in all of the cases? Yes RENEW the temperature control potentiometer. CHECK the operation of the system. If the system is still inoperative, RENEW the temperature control flap actuator. No LOCATE and REPAIR the break in the relevant circuit between the temperature control flap actuator and the A/C control assembly with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST G : AIR DISTRIBUTION FLAP ACTUATOR FOR ADDITIONAL HEATER INOPERATIVE (OPERATION OF ADDITIONAL BLOWER MOTOR OK) | NOTE:Before carrying out the check, make sure that the air distribution flap is mechanically OK. | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | G1: CHECK FUSE F50 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F50 (standard relay box). | | | Is the fuse OK? Yes No RENEW fuse F50. CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | G2: CHECK THE VOLTAGE AT FUSE F50 | | | 1 Connect Fuse F50 (standard relay box). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F50 (10 A) and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F50 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | G3: CHECK THE VOLTAGE AT THE ACTUATOR FOR THE ADDITIONAL HEATER AIR DISTRIBUTION FLAP | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CHA09 from the actuator for the additional heater air distribution flap. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the actuator for the additional heater air distribution flap, connector CHA09, pin 7, circuit CB150U (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in the circuit between the actuator for the additional heater air distribution flap and fuse F50 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | G4: CHECK THE GROUND CONNECTION OF THE ACTUATOR FOR THE ADDITIONAL HEATER AIR DISTRIBUTION FLAP | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the actuator for the additional heater air distribution flap, connector CHA09, pin 8, circuit GD149AC (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and REPAIR the break in the circuit between the actuator for the additional heater air distribution flap and ground connection GP49 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | G5: CHECK THE VOLTAGE AT THE ADDITIONAL HEATER CONTROL ASSEMBLY | | | 1 Disconnect Connector CHA05B from the additional heater control assembly. | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between the additional heater control assembly, connector CHA05B, pin 4, circuit CB150G (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and RECTIFY the open circuit between the additional heater control assembly and soldered connection S2B150D with the aid of the Wiring Diagrams. CHECK the operation of the system. | | G6: CHECK THE GROUND CONNECTION OF THE ADDITIONAL HEATER CONTROL ASSEMBLY | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the additional heater control assembly, connector CHA05B, pin 8, circuit GD149P (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes No LOCATE and RECTIFY the open circuit between the additional heater control assembly and soldered connection S4D149F with the aid of the Wiring Diagrams. CHECK the operation of the system. | | G7: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL HEATER CONTROL ASSEMBLY AND THE ACTUATOR FOR THE ADDITIONAL HEATER AIR DISTRIBUTION FLAP FOR OPEN CIRCUIT | | | 1 Measure the resistance between the additional heater control assembly, connector CHA05B, pin 5, circuit VHA09A (VT/BN), wiring harness side and the actuator for the additional heater air distribution flap, connector CHA09, pin 3, circuit VHA09D (VT/BN), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the actuator for the additional heater air distribution flap CHECK the operation of the system. If the system is still inoperative, RENEW the additional heater control assembly. No LOCATE and REPAIR the break in the circuit between the additional heater control assembly and the actuator for the additional heater air distribution flap with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST H : THE TEMPERATURE CONTROL IS INOPERATIVE WHEN THE ADDITIONAL HEATER CONTROL ASSEMBLY IS USED. | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | H1: CHECK FUSE F50 | | | 1 Ignition switch in position 0. | | | 2 CHECK Fuse F50 (standard relay box). | | | Is the fuse OK? Yes No RENEW fuse F50. CHECK the operation of the system. If the fuse blows again, LOCATE and REPAIR the short using the Wiring Diagrams. | | H2: CHECK THE VOLTAGE AT FUSE F50 | | | 1 Connect Fuse F50 (standard relay box). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F50 (10 A) and ground. | | | Does the meter display battery voltage? Yes No REPAIR the voltage supply to fuse F50 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | H3: CHECK THE VOLTAGE AT THE ADDITIONAL HEATER CONTROL VALVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH431 from the additional heater control valve. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the additional heater control valve, connector CH431, pin 1, circuit CB150X (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the open circuit between the additional heater control valve and actuator fuse F50 using the Wiring Diagrams. CHECK the operation of the system. | | H4: MEASURE THE VOLTAGE AT THE ADDITIONAL HEATER CONTROL VALVE MODULE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH107 from the additional heater control valve module. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the additional heater control valve module, connector CH107, pin 2, circuit CB150V (YE/OG), wiring harness side and ground. | | | 5 Measure the voltage between the additional heater control valve module, connector CH107, pin 12, circuit CB150W (YE/OG), wiring harness side and ground. | | | Is battery voltage measured in both cases? Yes No LOCATE and REPAIR the break in the relevant circuit between the additional heater control valve module and soldered connection S4B150E for the additional heater with the aid of the Wiring Diagrams. CHECK the operation of the system. | | H5: CHECK THE GROUND CONNECTION OF THE ADDITIONAL HEATER CONTROL VALVE MODULE | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the additional heater control valve module, connector CH107, pin 1, circuit GD149AD (BK/GY), wiring harness side and ground. | | | 3 Measure the resistance between the additional heater control valve module, connector CH107, pin 6, circuit GD149AB (BK/GY), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms measured in both cases? Yes No LOCATE and REPAIR the break in the relevant circuit between the additional heater control valve module and soldered connection S4D149E with the aid of the Wiring Diagrams. CHECK the operation of the system. | | H6: CHECK THE CIRCUIT OF THE ADDITIONAL HEATER CONTROL VALVE | | | 1 Connect Connector CH431 to the additional heater control valve. | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between the additional heater control valve module, connector CH107, pin 5, circuit ZA346A (OG/WH), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No | | H7: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL HEATER CONTROL VALVE AND THE ADDITIONAL HEATER CONTROL VALVE MODULE FOR OPEN CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH431 from the additional heater control valve. | | | 3 Measure the resistance between the additional heater control valve, connector CH431, pin 2, circuit ZA346A (OG/WH), wiring harness side and the additional heater control valve module, connector CH107, pin 5, circuit ZA346A (OG/WH), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional heater control valve. CHECK the operation of the system. No LOCATE and REPAIR the break in circuit ZA346A (OG/WH) between the additional heater control valve and the additional heater control valve module with the aid of the Wiring Diagrams. CHECK the operation of the system. | | H8: CHECK THE CIRCUIT BETWEEN THE ADDITIONAL HEATER CONTROL VALVE MODULE AND THE ADDITIONAL HEATER CONTROL ASSEMBLY FOR OPEN CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CHA05B from the additional heater control assembly. | | | 3 Measure the resistance between the additional heater control valve module, connector CH107, pin 7, circuit CHA04D (GN/WH), wiring harness side and the additional heater control assembly, connector CHA05B, pin 6, circuit CHA04A (GN/WH), wiring harness side. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the additional heater control valve module. CHECK the operation of the system. If the system is still inoperative, RENEW the additional heater control assembly. No LOCATE and RECTIFY the open circuit between the additional heater control valve module and the additional heater control assembly with the aid of the Wiring Diagrams. CHECK the operation of the system. | | PINPOINT TEST I : RECIRCULATED AIR FLAP INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | I1: CHECK THE VACUUM SUPPLY AT THE RECIRCULATED AIR FLAP ACTUATOR | | | 1 Ignition switch in position 0. | | | 2 Disconnect Vacuum hose from the recirculated air flap actuator. | | | 3 Connect a vacuum pressure gauge to the vacuum hose of the air recirculation flap actuator. | | | 4 Ignition switch in position III. 5 Run the engine at idle speed. | | | 6 Set the air distribution control switch to "FOOTWELL". | | | 7 Switch on recirculating air mode. | | | 8 Check the vacuum at the vacuum hose of the air recirculation flap actuator. | | | Is there a vacuum? Yes No | | I2: CHECK THE AIR RECIRCULATION FLAP ACTUATOR FOR LEAK-TIGHTNESS AND OPERATION | | | 1 Ignition switch in position 0. | | | 2 Apply a vacuum with a vacuum pump to the air recirculation flap actuator. | | | 3 Check the operation and leak-tightness of the air recirculation flap actuator. | | | Is the air recirculation flap actuator OK? Yes CHECK the mechanical operation of the air recirculation flap and REPAIR as necessary. CHECK the operation of the system. No RENEW the recirculated air flap actuator. CHECK the operation of the system. | | I3: CHECK THE VACUUM SUPPLY AT THE CONTROL ASSEMBLY FOR THE CLIMATE CONTROL SYSTEM | | | 1 Ignition switch in position 0. | | | 2 Disconnect Vacuum hose from the control assembly for the climate control system. | | | 3 Vacuum pressure gauge to the vacuum hose of the climate control system control assembly, connect a vacuum supply. | | | 4 Ignition switch in position III. 5 Run the engine at idle speed. | | | 6 Vacuum at the control assembly for the climate control system, check the vacuum supply. | | | Is there a vacuum? Yes CHECK and REPAIR the vacuum line between the control assembly for the climate control system and the air recirculation flap actuator. CHECK the operation of the system. If the vacuum line is OK, CHECK the control assembly for the climate control system and RENEW it if necessary. No CHECK and REPAIR the vacuum line between the control assembly for the climate control system and the engine. CHECK the operation of the system. | | PINPOINT TEST J : NO HEATING POWER | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | J1: DETERMINE THE FAULT CONDITION | | | 1 Ignition switch in position III. | | | 2 Run the engine until the temperature gauge indicates "NORMAL". | | | 3 Check the operation of the heater. | | | Is the heater permanently cold? Yes No CHECK whether the coolant hoses are routed correctly. BLEED the cooling system if necessary. If the cooling system is OK, RENEW the coolant shut-off valve. CHECK the operation of the system. | | J2: CHECK THE VACUUM SUPPLY AT THE COOLANT SHUT-OFF VALVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Vacuum hose from the coolant shut-off valve. | | | 3 Vacuum pressure gauge to the vacuum hose of the coolant shut-off valve, connect a vacuum supply. | | | 4 Ignition switch in position III. 5 Run the engine at idle speed. | | | 6 Slowly alter the setting of the temperature controller from full cold to full heat and back again several times. | | | 7 Vacuum at the coolant shut-off valve, check the vacuum supply. | | | Does the display alternate between vacuum and normal pressure? Yes CHECK whether the coolant hoses are routed correctly. BLEED the cooling system if necessary. If the cooling system is OK, RENEW the coolant shut-off valve. CHECK the operation of the system. No | | J3: CHECK THE VACUUM SUPPLY TO THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Vacuum hose from the solenoid valve of the coolant shut-off valve. | | | 3 Vacuum pressure gauge to the vacuum hose of the solenoid valve of the coolant shut-off valve, connect a vacuum supply. | | | 4 Ignition switch in position III. 5 Run the engine at idle speed. | | | 6 Vacuum at the solenoid valve of the coolant shut-off valve, check the vacuum supply. | | | Is there a vacuum? Yes CHECK and REPAIR the vacuum line between the solenoid valve of the coolant shut-off valve and the coolant shut-off valve. CHECK the operation of the system. If the vacuum line is OK, GO to J4. No CHECK and REPAIR the vacuum line between the solenoid valve of the coolant shut-off valve and the engine. CHECK the operation of the system. | | J4: CHECK THE VOLTAGE AT THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH226 from the solenoid valve of the coolant shut-off valve . | | | 3 Ignition switch in position II. | | | 4 Set the temperature control to maximum cold. | | | 5 Measure the voltage between the coolant shut-off valve, connector CH226, pin 2, circuit ZA340A (OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No | | J5: CHECK THE GROUND CONNECTION OF THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the solenoid valve of the coolant shut-off valve, connector CH226, pin 1, circuit GD122D (BK), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes RENEW the solenoid valve of the coolant shut-off valve CHECK the operation of the system. No LOCATE and RECTIFY the break in the circuit between the solenoid valve of the coolant shut-off valve and ground connection GP22 with the aid of the Wiring Diagrams. CHECK the operation of the system. | | J6: CHECK THE VOLTAGE AT THE SWITCH OF THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE | | | 1 Ignition switch in position 0. | | | 2 Disconnect Connector CH422 from the switch of the solenoid valve of the coolant shut-off valve . | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between the switch of the solenoid valve of the coolant shut-off valve, connector CH422, pin 2, circuit CB150L (YE/OG), wiring harness side and ground. | | | Does the meter display battery voltage? Yes No LOCATE and REPAIR the break in circuit CB150L (YE/OG) between the switch of the solenoid valve of the coolant shut-off valve and soldered connection S2B150B with the aid of the Wiring Diagrams. CHECK the operation of the system. | | J7: CHECK THE CIRCUIT BETWEEN THE SWITCH OF THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE AND THE SOLENOID VALVE OF THE COOLANT SHUT-OFF VALVE FOR OPEN CIRCUIT. | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the switch of the solenoid valve of the coolant shut-off valve, connector CH422, pin 1, circuit ZA340D (OG), wiring harness side and the solenoid valve of the coolant shut-off valve, connector CH226, pin 2, circuit ZA340A (OG), wiring harness side and ground. | | | Is a resistance of less than 2 Ohms registered? Yes CHECK the mechanical actuation of the switch of the solenoid valve of the coolant shut-off valve and REPAIR it if necessary. If the mechanical actuation is OK, RENEW the switch of the solenoid valve of the coolant shut-off valve. CHECK the operation of the system. No LOCATE and RECTIFY the break in the circuit between the switch of the solenoid valve of the coolant shut-off valve and the solenoid valve of the coolant shut-off valve with the aid of the Wiring Diagrams. CHECK the operation of the system. | |
