| Diagnosis and Testing Refer to Wiring Diagrams Section 417-01, for schematic and connector information. Special Tool(s) | | Terminal probe kit 29-011A | Inspection and Verification - Verify the customer concern.
- Visually inspect for obvious signs of electrical damage.
Visual Inspection Chart | Electrical | - Fuse(s)
- Bulb(s)
- Electrical connector(s)
- Wiring harness
| - If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart Symptom Chart | Symptom | Possible Sources | Action | | Both headlamps (low and high beam) are inoperative | * Fuse(s) * Circuit(s) * Steering column multifunction switch * Central junction box (CJB) | * | | The low beam are inoperative | * Fuse(s) * Circuit(s) * Low beam relay * Steering column multifunction switch * Central junction box (CJB) * Headlamp switch | * | | The high beam are inoperative | * Fuse(s) * Circuit(s) * High beam relay * Steering column multifunction switch * Central junction box (CJB) * Headlamp switch | * | | One low beam is inoperative | * Fuse(s) * Circuit(s) * Steering column multifunction switch * Central junction box (CJB) * Headlamp | * | | One high beam is inoperative | * Fuse(s) * Circuit(s) * Low beam relay * Steering column multifunction switch * Central junction box (CJB) * Headlamp | * | | The headlamps (low or high beam) are on continuously | * Fuse * Circuit(s) * Steering column multifunction switch * Instrument cluster * High beam relay * Low beam relay * Central junction box (CJB) | * | | The flash-to-pass feature is inoperative | * Fuse(s) * Circuit(s) * Central junction box (CJB) * Steering column multifunction switch * High beam relay | * | Pinpoint Tests NOTE:Use a digital multimeter for all electrical measurements. | PINPOINT TEST A : BOTH HEADLAMPS (LOW AND HIGH BEAM) ARE INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | A1: CHECK THE POWER SUPPLY OF THE HEADLAMP SWITCH FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Disconnect headlamp switch from connector C120. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between headlamp switch, connector C120, pin 8, circuit 15-DD1 (GN/YE), wiring harness side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between splice S312 and headlamp switch by using the wiring diagrams. TEST the system for normal operation. | | A2: CHECK THE HEADLAMP SWITCH | | | 1 Ignition switch in position 0. | | | 2 Connect a fused jumper wire (15 A) at the headlamp switch, connector C120, between pin 8, circuit 15-DD1 (GN/YE) and pin 6, circuit 29S-LE14 (OG), wiring harness side. | | | 3 Ignition switch in position II. | | | 4 TURN ON the steering column multifunction switch to the low beam position. | | | 5 CHECK the low beam. | | | Do the low beam illuminate? Yes INSTALL a new headlamp switch. TEST the system for normal operation. No | | A3: CHECK THE STEERING COLUMN MULTIFUNCTION SWITCH | | | 1 Ignition switch in position 0. | | | 2 Connect headlamp switch to connector C120. | | | 3 Disconnect steering column multifunction switch from connector C178. | | | 4 Connect a fused jumper wire (15 A) at the steering column multifunction switch, connector C178, between pin 8, circuit 29S-LE14 (OG) and pin 9, circuit 15S-LE19 (GN/BU), wiring harness side. | | | 5 Ignition switch in position II. | | | 6 TURN ON the headlamp switch to head position. | | | 7 CHECK the low beam. | | | Do the low beam illuminate? Yes INSTALL a new steering column multifunction switch. TEST the system for normal operation. No LOCATE and REPAIR the open circuit between the headlamp switch and steering column multifunction switch by using the wiring diagrams. TEST the system for normal operation. | | PINPOINT TEST B : THE LOW BEAMS ARE INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | B1: CHECK FUSE F1.3 (BJB) | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F1.3 (20 A) (BJB). | | | 3 CHECK fuse F1.3 (20 A) (BJB). | | | Is the fuse OK? Yes No INSTALL a new fuse F1.3 (20 A) (BJB) and TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground by using the wiring diagrams. TEST the system for normal operation. | | B2: CHECK THE VOLTAGE AT FUSE F1.3 (BJB) | | | 1 Connect fuse F1.3 (20 A) (BJB). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F1.3 (20 A) (BJB) and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open in the power supply of fuse F1.3 (BJB) by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. | | B3: CHECK THE STEERING COLUMN MULTIFUNCTION SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect steering column multifunction switch from connector C178. | | | 3 Connect a fused jumper wire (15 A) at the steering column multifunction switch, connector C178, between pin 8, circuit 29S-LE14 (OG) and pin 9, circuit 15S-LE19 (GN/BU), wiring harness side. | | | 4 Ignition switch in position II. | | | 5 CHECK the low beams. | | | Do the low beams illuminate? Yes INSTALL a new steering column multifunction switch. TEST the system for normal operation. No | | B4: CHECK THE POWER SUPPLY OF THE LOW BEAM RELAY FOR OPEN, LOAD CIRCUIT | | | 1 Ignition switch in position 0. | | | 2 Disconnect low beam relay from socket C1015. | | | 3 Ignition switch in position II. | | | 4 Measure the voltage between low beam relay, socket C1015, pin 3, circuit 30-LE20 (RD), BJB-side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between fuse F1.3 (BJB) and low beam relay by using the wiring diagrams. TEST the system for normal operation. | | B5: CHECK THE GROUND SUPPLY OF THE LOW BEAM RELAY FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between low beam relay, socket C1015, pin 2, circuit 31-LE19 (BK), BJB-side and ground. | | | Is the resistance less than 2 ohms? Yes No LOCATE and REPAIR the open circuit between the low beam relay and splice S211 by using the wiring diagrams. TEST the system for normal operation. | | B6: CHECK THE COMMON POWER SUPPLY OF THE LOW BEAMS FOR OPEN | | | 1 Measure the resistance between low beam relay, socket C1015, pin 5, circuit 30S-LE20 (RD/OG), BJB-side and ground. | | | Is the resistance less than 10,000 ohms? Yes No LOCATE and REPAIR the open circuit between the low beam relay and splice S292 by using the wiring diagrams. TEST the system for normal operation. | | B7: CHECK THE CONTROL CIRCUIT OF THE LOW BEAM RELAY FOR OPEN | | | 1 Measure the resistance between steering column multifunction switch, connector C178, pin 9, circuit 15S-LE19 (GN/BU), wiring harness side and low beam relay, socket C1015, pin 1, circuit 15S-LE19 (GN/BU), BJB-side. | | | Is the resistance less than 2 ohms? Yes INSTALL a new low beam relay. TEST the system for normal operation. No LOCATE and REPAIR the open circuit between the steering column multifunction switch and low beam relay by using the wiring diagrams. TEST the system for normal operation. | | PINPOINT TEST C : THE HIGH BEAM ARE INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | C1: CHECK FUSE F1.9 (BJB) | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F1.9 (20A) (BJB). | | | 3 CHECK fuse F1.9 (20A) (BJB). | | | Is the fuse OK? Yes No INSTALL a new fuse F1.9 (20 A) (BJB) and TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground by using the wiring diagrams. TEST the system for normal operation. | | C2: CHECK THE VOLTAGE AT FUSE F1.9 (BJB) | | | 1 Connect fuse F1.9 (20 A) (BJB). | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between fuse F1.9 (20 A) (BJB) and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open in the power supply of fuse F1.9 (BJB) by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. | | C3: CHECK THE STEERING COLUMN MULTIFUNCTION SWITCH | NOTE:The fused jumper wire remains connected for the next teststep. | | | 1 Ignition switch in position 0. | | | 2 Disconnect steering column multifunction switch from connector C178. | | | 3 Connect a fused jumper wire (15 A) at the steering column multifunction switch, connector C178, between pin 8, circuit 29S-LE14 (OG) and pin 7, circuit 15S-DC4 (GN/BU), wiring harness side. | | | 4 Ignition switch in position II. | | | 5 TURN ON the headlamp switch to head position. | | | 6 CHECK the high beam and the high beam indicator lamp. | | | Do the high beam illuminate? Yes INSTALL a new steering column multifunction switch. TEST the system for normal operation. No - The high beam indicator lamp is illuminated: GO to C4. - The high beam indicator lamp is not illuminated: LOCATE and REPAIR the open circuit 15S-DC4 (GN/BU) between the steering column multifunction switch and splice S256 by using the wiring diagrams. TEST the system for normal operation. | | C4: CHECK THE POWER SUPPLY OF THE HIGH BEAM RELAY FOR OPEN, CONTROL CIRCUIT | | | 1 TURN ON the headlamp switch to head position. | | | 2 Ignition switch in position 0. | | | 3 Disconnect high beam relay from socket C1016. | | | 4 Ignition switch in position II. | | | 5 Measure the voltage between high beam relay, socket C1016, pin 1, circuit 15S-LE12 (GN/YE), BJB-side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open in circuit(s) between splice S256 and high beam relay by using the wiring diagrams. TEST the system for normal operation. | | C5: CHECK THE POWER SUPPLY OF THE HIGH BEAM RELAY FOR OPEN, LOAD CIRCUIT | | | 1 Measure the voltage between high beam relay, socket C1016, pin 3, circuit 30-LE13 (RD), BJB-side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between fuse F1.9 (BJB) and high beam relay by using the wiring diagrams. TEST the system for normal operation. | | C6: CHECK THE GROUND SUPPLY OF THE HIGH BEAM RELAY FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between high beam relay, socket C1016, pin 2, circuit 31-LE12 (BK), BJB-side and ground. | | | Is the resistance less than 2 ohm? Yes No LOCATE and REPAIR the open circuit between the high beam relay and splice S211 by using the wiring diagrams. TEST the system for normal operation. | | C7: CHECK THE COMMON POWER SUPPLY OF THE HIGH BEAM FOR OPEN | | | 1 Measure the resistance between high beam relay, socket C1016, pin 5, circuit 30S-LE13 (RD/BU), BJB-side and ground. | | | Is the resistance less than 10,000 ohms? Yes INSTALL a new high beam relay. TEST the system for normal operation. No LOCATE and REPAIR the open in circuit(s) between the high beam relay and splice S231 by using the wiring diagrams. TEST the system for normal operation. | | PINPOINT TEST D : ONE LOW BEAM IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | D1: DETERMINE THE INOPERATIVE LOW BEAM | | | 1 Ignition switch in position II. | | | 2 TURN ON the low beam. | | | 3 CHECK the low beam. | | | Is the low beam, left-hand side inoperative? Yes No The low beam, right-hand side is inoperative: GO to D6. | | D2: CHECK THE FUSE F1.24 (BJB) | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F1.24 (10A) (BJB). | | | 3 CHECK fuse F1.24 (10A) (BJB). | | | Is the fuse OK? Yes No INSTALL a new fuse F1.24 (10 A) and TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground by using the wiring diagrams. TEST the system for normal operation. | | D3: CHECK THE VOLTAGE AT FUSE F1.24 (BJB) | | | 1 Connect fuse F1.24 (10 A) (BJB). | | | 2 TURN ON the low beam. | | | 3 Measure the voltage between fuse F1.24 (10 A) (BJB) and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit 30S-DA9 (RD/OG), between splice S292 and fuse F1.24 (BJB) by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. | | D4: CHECK THE POWER SUPPLY OF THE LOW BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Disconnect headlamp, left-hand side from connector C119. | | | 3 Ignition switch in position II. | | | 4 TURN ON the low beam. | | | 5 Measure the voltage between headlamp, left-hand side, connector C119, pin 7, circuit 30S-LE16 (RD/BK), wiring harness side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between fuse F1.24 (BJB) and headlamp by using the wiring diagrams. TEST the system for normal operation. | | D5: CHECK THE GROUND SUPPLY OF THE LOW BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between headlamp, left-hand side, connector C119, pin 4, circuit 31-LE31 (BK), wiring harness side and ground. | | | Is the resistance less than 2 ohms? Yes CHECK the headlamp. If necessary INSTALL a new one. TEST the system for normal operation. No LOCATE and REPAIR the open in circuit(s) between the headlamp and splice S223 by using the wiring diagrams. TEST the system for normal operation. | | D6: CHECK FUSE F1.23 (BJB) | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F1.23 (10 A) (BJB). | | | 3 CHECK fuse F1.23 (10A) (BJB). | | | Is the fuse OK? Yes No INSTALL a new fuse F1.23 (10 A) (BJB) and TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground by using the wiring diagrams. TEST the system for normal operation. | | D7: CHECK THE VOLTAGE AT FUSE F1.23 (BJB) | | | 1 Connect fuse F1.23 (10 A) (BJB). | | | 2 Ignition switch in position II. | | | 3 TURN ON the low beam. | | | 4 Measure the voltage between fuse F1.23 (10 A) (BJB) and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit 30S-DA10 (RD/GN), between splice S292 and fuse F1.23 (BJB) by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. | | D8: CHECK THE POWER SUPPLY OF THE LOW BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Disconnect headlamp, right-hand side from connector C118. | | | 3 Ignition switch in position II. | | | 4 TURN ON the low beam. | | | 5 Measure the voltage between headlamp, right-hand side: - long wheelbase chassis cab: connector C118, pin 7, circuit 30S-LE16 (RD/BK), wiring harness side and ground.
- all other models: connector C118, pin 7, circuit 30S-LE23 (RD/WH), wiring harness side and ground.
| | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between fuse F1.23 (BJB) and headlamp by using the wiring diagrams. TEST the system for normal operation. | | D9: CHECK THE GROUND SUPPLY OF THE LOW BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between headlamp, right-hand side: - long wheelbase chassis cab: connector C118, pin 4, circuit 31-LE31 (BK), wiring harness side and ground.
- all other models: connector C118, pin 4, circuit 31-LE30 (BK), wiring harness side and ground.
| | | Is the resistance less than 2 ohms? Yes CHECK the headlamp. If necessary INSTALL a new one. TEST the system for normal operation. No LOCATE and REPAIR the open in circuit(s) between the headlamp and splice S300 by using the wiring diagrams. TEST the system for normal operation. | | PINPOINT TEST E : ONE HIGH BEAM IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | E1: DETERMINE THE INOPERATIVE HIGH BEAM | | | 1 Ignition switch in position II. | | | 2 TURN ON the high beam. | | | 3 CHECK the high beam. | | | Is the high beam, left-hand side inoperative? Yes No The high beam, right-hand side is inoperative: GO to E6. | | E2: CHECK THE POWER SUPPLY OF THE HIGH BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Disconnect headlamp, left-hand side from connector C119. | | | 3 Ignition switch in position II. | | | 4 TURN ON the high beam. | | | 5 Measure the voltage between headlamp, left-hand side, connector C119, pin 6, circuit 30S-LE15 (RD/GN), wiring harness side and ground. | | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between splice S231 and headlamp by using the wiring diagrams. TEST the system for normal operation. | | E3: CHECK THE GROUND SUPPLY OF THE HIGH BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position II. | | | 2 TURN ON the turn signal lamps, left-hand side. | | | 3 CHECK the turn signal lamps. | | | Do the left-hand turn signal lamp, front operate? Yes No LOCATE and REPAIR the open circuit between splice S223 and ground G7 by using the wiring diagrams. TEST the system for normal operation. | | E4: CHECK THE GROUND SUPPLY OF THE HIGH BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Measure the resistance between headlamp, left-hand side, connector C119, pin 4, circuit 31-LE31 (BK), wiring harness side and ground. | | | Is the resistance less than 2 ohms? Yes No LOCATE and REPAIR the open circuit between the headlamp and splice S223 by using the wiring diagrams. TEST the system for normal operation. | | E5: CHECK THE GROUND SUPPLY OF THE HIGH BEAM LEFT-HAND SIDE FOR OPEN | | | 1 Measure the resistance between headlamp, left-hand side, connector C119, pin 1, circuit 31-LF7 (BK), wiring harness side and ground. | | | Is the resistance less than 2 ohms? Yes CHECK the headlamp. If necessary INSTALL a new one. TEST the system for normal operation. No LOCATE and REPAIR the open circuit between the headlamp and splice S223 by using the wiring diagrams. TEST the system for normal operation. | | E6: CHECK THE POWER SUPPLY OF THE HIGH BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Disconnect headlamp, right-hand side from connector C118. | | | 3 Ignition switch in position II. | | | 4 TURN ON the high beam. | | | 5 Measure the voltage between headlamp, right-hand side: - long wheel base chassis cab: connector C118, pin 6, circuit 30S-LE15 (RD/GN), wiring harness side and ground.
- all other models: connector C118, pin 6, circuit 30S-LE22 (RD/BK), wiring harness side and ground.
| | | Is battery voltage indicated? Yes No LOCATE and REPAIR the open circuit between splice S231 and headlamp by using the wiring diagrams. TEST the system for normal operation. | | E7: CHECK THE GROUND SUPPLY OF THE HIGH BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position II. | | | 2 TURN ON the turn signal right-hand side. | | | 3 CHECK the turn signal lamps. | | | Do the right-hand turn signal lamp, front operate? Yes No LOCATE and REPAIR the open circuit between splice S300 and ground G6 by using the wiring diagrams. TEST the system for normal operation. | | E8: CHECK THE GROUND SUPPLY OF THE HIGH BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between headlamp, right-hand side: - long wheelbase chassis cab: connector C118, pin 4, circuit 31-LE31 (BK), wiring harness side and ground.
- all other models: connector C118, pin 4, circuit 31-LE30 (BK), wiring harness side and ground.
| | | Is the resistance less than 2 ohms? Yes No LOCATE and REPAIR the open circuit between the headlamp and splice S300 by using the wiring diagrams. TEST the system for normal operation. | | E9: CHECK THE GROUND SUPPLY OF THE HIGH BEAM RIGHT-HAND SIDE FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between headlamp, right-hand side: - long wheelbase chassis cab: connector C118, pin 1circuit 31-LF7 (BK), wiring harness side and ground.
- all other models: connector C118, pin 1circuit 31-LF16 (BK), wiring harness side and ground.
| | | Is the resistance less than 2 ohms? Yes CHECK the headlamp. If necessary INSTALL a new one. TEST the system for normal operation. No LOCATE and REPAIR the open circuit between the headlamp and splice S300 by using the wiring diagrams. TEST the system for normal operation. | | PINPOINT TEST F : THE HEADLAMPS (LOW OR HIGH BEAM) ARE ON CONTINUOUSLY | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | F1: DETERMINE THE FAULT CONDITION | | | 1 TURN OFF the headlamps. | | | 2 TURN ON the steering column multifunction switch to the neutral/low beam position. | | | 3 Ignition switch in position II. | | | 4 CHECK the headlamps. | | | Are the low beam on continuously? Yes No | | F2: NARROW DOWN THE LOCATION OF THE SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect low beam relay from socket C1015. | | | 3 Ignition switch in position II. | | | 4 CHECK the headlamps. | | | Are the low beam on continuously? Yes No | | F3: RULE OUT LOW BEAM RELAY AS POSSIBLE CAUSE FOR A SHORT TO POWER | | | 1 Measure the voltage between low beam relay, socket C1015, pin 1, circuit 15S-LE19 (GN/BU), BJB-side and ground. | | | Is battery voltage indicated? Yes No INSTALL a new low beam relay. TEST the system for normal operation. | | F4: RULE OUT HEADLAMP SWITCH AS POSSIBLE CAUSE FOR A SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Connect low beam relay to socket C1015. | | | 3 Disconnect headlamp switch from connector C120. | | | 4 Ignition switch in position II. | | | 5 CHECK the low beam. | | | Are the low beam on continuously? Yes No INSTALL a new headlamp switch. TEST the system for normal operation. | | F5: RULE OUT STEERING COLUMN MULTIFUNCTION SWITCH AS POSSIBLE CAUSE FOR A SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect steering column multifunction switch from connector C178. | | | 3 Ignition switch in position II. | | | 4 CHECK the low beam. | | | Are the low beam on continuously? Yes LOCATE and REPAIR the short to power in the circuit 15S-LE19 (GN/BU) between steering column multifunction switch and low beam relay by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. No | | F6: NARROW DOWN THE LOCATION OF THE SHORT TO POWER | | | 1 Measure the voltage between steering column multifunction switch, connector C178, pin 8, circuit 29S-LE14 (OG), wiring harness side and ground. | | | Is battery voltage indicated? Yes LOCATE and REPAIR the short to power in the circuit between headlamp switch and steering column multifunction switch by using the wiring diagrams. TEST the system for normal operation. No INSTALL a new steering column multifunction switch. TEST the system for normal operation. | | F7: NARROW DOWN THE LOCATION OF THE SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F1.24 (10A) (BJB). | | | 3 Disconnect fuse F1.23 (10A) (BJB). | | | 4 Ignition switch in position II. | | | 5 CHECK the headlamps. | | | Does one low beam illuminate? Yes - Low beam, left-hand side is illuminated: LOCATE and REPAIR the short to power in the circuit 30S-LE16 (RD/BK) by using the wiring diagrams. TEST the system for normal operation. - Low beam right-hand side is illuminated: LOCATE and REPAIR the short to power in the circuit 30S-LE23 (RD/WH) or 30S-LE16 (RD/BK) (long wheelbase chassis cab only) by using the wiring diagrams. TEST the system for normal operation. No LOCATE and REPAIR the short to power in the circuits connected with splice S292 by using the wiring diagrams. TEST the system for normal operation. | | F8: NARROW DOWN THE LOCATION OF THE SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect high beam relay from socket C1016. | | | 3 Ignition switch in position II. | | | 4 CHECK the headlamps. | | | Do the high beam illuminate? Yes LOCATE and REPAIR the short to power in the circuits connected with splice S231 by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. No | | F9: DETERMINE THE SHORT TO POWER CONDITION | | | 1 Check the high beam indicator lamp in the instrument cluster. | | | Does the indicator lamp illuminate? Yes No INSTALL a new high beam relay. TEST the system for normal operation. | | F10: RULE OUT STEERING COLUMN MULTIFUNCTION SWITCH AS POSSIBLE CAUSE FOR A SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect steering column multifunction switch from connector C178. | | | 3 Ignition switch in position II. | | | 4 Check the high beam indicator lamp in the instrument cluster. | | | Does the indicator lamp illuminate? Yes No INSTALL a new steering column multifunction switch. TEST the system for normal operation. | | F11: RULE OUT INSTRUMENT CLUSTER AS POSSIBLE CAUSE FOR A SHORT TO POWER | | | 1 Ignition switch in position 0. | | | 2 Disconnect fuse F2.1 (15 A) (CJB). | | | 3 Disconnect fuse F2.10 (15 A) (CJB). | | | 4 Disconnect fuse F2.27 (5 A) (CJB). | | | 5 Connect high beam relay to socket C1016. | | | 6 Ignition switch in position II. | | | 7 CHECK the headlamps. | | | Do the high beam illuminate? Yes LOCATE and REPAIR the short to power in the circuits connected with splice S256 by using the wiring diagrams. TEST the system for normal operation. If necessary CHECK the BJB and INSTALL a new one. TEST the system for normal operation. No INSTALL a new instrument cluster. TEST the system for normal operation. | | PINPOINT TEST G : THE FLASH-TO-PASS FEATURE IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | G1: CHECK THE STEERING COLUMN MULTIFUNCTION SWITCH | | | 1 Ignition switch in position II. | | | 2 TURN ON the high beam. | | | 3 CHECK the headlamps. | | | Do the high beam illuminate? Yes No | | G2: CHECK THE POWER SUPPLY OF THE STEERING COLUMN MULTIFUNCTION SWITCH | | | 1 Ignition switch in position 0. | | | 2 Disconnect steering column multifunction switch from connector C178. | | | 3 Measure the voltage between steering column multifunction switch, connector C178, pin 6, circuit 15-LE14 (GN/RD), wiring harness side and ground. | | | Is battery voltage indicated? Yes INSTALL a new steering column multifunction switch. TEST the system for normal operation. No LOCATE and REPAIR the open circuit between splice S312 and steering column multifunction switch by using the wiring diagrams. TEST the system for normal operation. | |
