Ford Workshop Service and Repair Manuals

Inspection and Checking

Visual Inspection

Refrigerant Circuit - Quick Check

WARNING:The air conditioning system is filled with refrigerant R134a. Observe "Health and Safety Precautions". For further information
REFER to: Health and Safety Precautions (100-00 General Information, 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 condenser to the fixed orifice tube must be warm, but it should be cooler than the refrigerant line mentioned above.
• Determine the difference in temperature upstream and downstream of the 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 fan.
• The refrigerant line between the fixed orifice tube and the evaporator must be cold from the installation position of the fixed orifice tube. Depending on the weather, the refrigerant line may also be iced up on the outside.
• The refrigerant line between the evaporator and the A/C compressor including the suction accumulator must be cold.

Evaporator outlet line temperature test

To test the power of the A/C system, the temperature of the evaporator outlet line must be measured. The following preparations need to be made to do this:

• 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 performed using a non-contact thermometer. Incorrect readings can result from surface reflections.

Connect the temperature sensor (Fluke 80 PK-8) to the evaporator outlet line. Locate the temperature sensor as close 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 temperature measured is 4°C or lower, the A/C system is OK. If the temperature is higher, the A/C system may be under-filled. For further information
REFER to: Air Conditioning (A/C) System Recovery, Evacuation and Charging (412-00 Climate Control System - General Information, General Procedures).

Frequent faults and their causes

If there is a concern over inadequate air conditioning performance, make sure that the temperature control flap is operating correctly.

• No or poor cooling performance:
  -

  Blockage or narrowing of a refrigerant line or in the suction accumulator: The location of the blockage or narrowing can easily be located by temperature comparisons at the refrigerant lines and the suction accumulator. The blockage or restriction is located at the point where the temperature difference is identified. Note: A temperature difference in the area of the fixed orifice tube is normal. Once the location of the blockage or restriction has been detected, check the relevant component and renew if necessary.

• Sudden poor cooling performance (after the air conditioning has been switched off for approx. 5 minutes, the cooling performance returns to normal):
  -

  Cause is an iced-up fixed orifice tube caused by moisture in the refrigerant circuit. In order to ensure that moisture is completely removed from the refrigerant circuit, the suction accumulator must be renewed and the evacuation time must be extended to 2-3 hours. For further information, REFER to:

  Suction Accumulator (412-03 Air Conditioning, Removal and Installation),

  Air Conditioning (A/C) System Recovery, Evacuation and Charging (412-00 Climate Control System - General Information, General Procedures).

Fault memory interrogation without WDS - vehicles with electronic automatic temperature control (EATC) and vehicles built from 06/2003

NOTE:For vehicles built from 06/2003, fault memory interrogation is also possible via the climate control assembly in the case of automatic temperature control (ATC).

NOTE:NOTE: On vehicles equipped with a DVD navigation system with touchscreen, interrogation of the fault memory is only possible using WDS.

The climate control system features a self-diagnosis function which can detect and store both current permanent faults as well as intermittent faults which have occurred during normal operation of the vehicle. It is also possible to read out these faults via the display of the (E)ATC module. To start self-diagnosis or to read out the fault memory, the ignition key must be turned to the "ON" position and the battery voltage must be between 9 V and 16 V.

Activation of self-diagnosis

On the (E)ATC module, PRESS the "OFF" and "FOOTWELL" buttons simultaneously for at least 2 seconds, then PRESS "AUTO" within 1.5 seconds. The self-diagnosis which then starts lasts a few seconds. An animated display will appear during this time in the (E)ATC display. Any faults found are displayed in the form of trouble codes. Example: first of all, "93" flashes for 2 seconds, then "42" flashes for 2 seconds - DTC 9342 = internal control unit fault. If no faults are stored, then all of the segments in the display are actuated. The following table gives information on the possible DTCs and their corresponding meanings. By PRESSING the "DEFROST" button, the fault memory is cleared and diagnosis mode is ended. To end the diagnostic mode without clearing the DTCs, PRESS any other (E)ATC button.

Read out stored faults

On the (E)ATC module, PRESS the "OFF" and "FOOTWELL" buttons simultaneously for at least 2 seconds, then PRESS "HEADROOM" within 1.5 seconds. Any stored intermittent faults are output on the (E)ATC display and should be written down for safety. By PRESSING the "DEFROST" button, the fault memory is cleared and diagnosis mode is ended. To end the diagnostic mode without clearing the DTCs, PRESS any other button on the (E)ATC module.

Reading out the (E)ATC software version

On the (E)ATC module, PRESS the "OFF" and "FOOTWELL" buttons simultaneously for at least 2 seconds, then PRESS "A/C" within 1.5 seconds. The SW version is output on the (E)ATC display. The output mode is ended by PRESSING any button.

Update the software version

For vehicles up to 06/2003, it is possible to update the software of the EATC and of the ATC via the WDS. For this purpose it must be ensured that the WDS is equipped with the latest WDS software.

Fault Code Table

¹ Not on vehicles with manual temperature control

² Vehicles built from 06/2003

³ Not on vehicles with manual temperature control built before 06/2003

Symptom Chart

Symptom Chart

System Checks

A/C clutch relay

Check the refrigerant circuit - vehicles with diesel engine

Workshop Equipment

The following equipment is required for the tests:

• R-134a refrigerant center or set of R134a pressure gauges
• Stopwatch

Pinpoint Test: Refrigerant Circuit

WARNING:The air conditioning system is filled with refrigerant R134a. Observe "Health and Safety Precautions". For further information
REFER to: Health and Safety Precautions (100-00 General Information, Description and Operation).

NOTE:The following Pinpoint Test only applies to vehicles with compressors without low-pressure circuit control (vehicles with diesel engine only).

The following values must be determined:

• Low pressure
• High pressure
• Cycle time

Test Preparations

The following steps must be carefully followed to guarantee accurate test results.

WARNING:The manufacturer's instructions must be followed when connecting the R-134a refrigerant center or the set of R134a pressure gauges. Failure to observe this instruction can lead to injuries.

• Connect the R134a refrigerant center or set of R134a pressure gauges to the refrigerant circuit.
• Start the engine.
• Switch on the air-conditioning system.
• Switch on the air recirculation.
• Set the blower switch to "MAXIMUM".
• Run the engine for approx. 10 minutes at 1500 rpm.

Check the cycle time and system pressures

Allow the engine to run at 1500 rpm during the test.

Example:

• High pressure too low
• Low pressure normal
• Overall cycle time too short
• “A/C clutch ON” cycle time too short
• “A/C clutch OFF” cycle time too short

Fault cause: Refrigerant quantity insufficient.

Target values

The high and low pressure values and the cycle times are dependent upon the ambient temperature. The ambient temperature should be measured at a distance of 1 m from the vehicle.

The applicable tolerance range which describes the "normal" range for a measured value, lies between the upper and lower curves.

High pressure

Low pressure

A/C clutch switched on

A/C clutch switched off

Total cycle time

NOTE:The total cycle time is made up of the "A/C clutch ON" time and the "A/C clutch OFF" time.

Symptom Chart: Refrigerant Circuit