Pinpoint Test B: All The Hardwired DIMMABLE Illumination Is Inoperative
NOTE:
Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- B1 CHECK FOR RECORDED SJB DTCs FROM THE ON-DEMAND SELF-TEST
- Ignition OFF.
- Use the recorded results from the SJB self-test.
- Is DTC B2A33 or B29B8 recorded?
- Yes: VERIFY the SJB fuse 10 (15A) is OK. If OK, GO to B2 . If not OK, REFER to the SYSTEM WIRING DIAGRAMS - EXPEDITION , SYSTEM WIRING DIAGRAMS - EXPEDITION EL , SYSTEM WIRING DIAGRAMS - NAVIGATOR or SYSTEM WIRING DIAGRAMS - NAVIGATOR L article to identify the possible causes of the circuit short.
- No: GO to B2 .
- B2 BYPASS THE SJB NOTE: If the jumper wire fails, refer to the SYSTEM WIRING DIAGRAMS - EXPEDITION , SYSTEM WIRING DIAGRAMS - EXPEDITION EL , SYSTEM WIRING DIAGRAMS - NAVIGATOR or SYSTEM WIRING DIAGRAMS - NAVIGATOR L article to identify the possible causes of the circuit short. Run the on-demand self-test (required to clear certain DTCs). Correct any unresolved DTCs. Clear all DTCs. Test the system for normal operation.
- Disconnect: SJB C2280b.
- For DTC B2A32 or DTC B2A33, connect a fused jumper wire between the SJB C2280b-39, circuit VLN18 (BU/WH) and battery positive.
- For DTC B29B7 or DTC B29B8, connect a fused jumper wire between the SJB C2280b-52, circuit VLN04 (VT/GY) and battery positive.
- Do(es) the backlighting component(s) illuminate?
- Yes: REMOVE the jumper wire. GO to B5.
- No:
For Navigator, if the auxiliary climate control is inoperative, REMOVE the jumper wire. GO to B3
.
For all others, REMOVE the jumper wire. REPAIR circuit VLN18 (BU/WH) or circuit VLN04 (VT/GY) for an open. CLEAR the DTCs. REPEAT the self-test.
- B3 CHECK FOR VOLTAGE TO THE AUXILIARY CLIMATE CONTROL MODULE
- Connect: SJB C2280b.
- Disconnect: Auxiliary Climate Control Assembly C3198.
- Place the headlamp switch in the PARKING LAMPS ON position.
- Rotate the instrument panel dimmer switch to the full illumination position.
- Measure the voltage between the auxiliary climate control assembly C3198-1, circuit VLN18 (BU/WH), harness side and ground.
- Is the voltage greater than 10 volts?
- Yes: GO to B4 .
- No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
- B4 CHECK FOR VOLTAGE TO THE AUXILIARY CLIMATE CONTROL MODULE USING THE CONNECTOR GROUND
- Measure the voltage between the auxiliary climate control assembly C3198-3, circuit VLN18 (BU/WH), harness side and the auxiliary climate control assembly C3198-3, circuit GD143 (BK/VT), harness side.
- Is the voltage greater than 10 volts?
- Yes:
INSTALL a new auxiliary climate control assembly. REFER to AUXILIARY CLIMATE CONTROL
. CLEAR the DTCs. REPEAT the self-test.
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
- No: REPAIR circuit GD143 (BK/VT) for an open. CLEAR the DTCs. REPEAT the self-test.
- B5 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new SJB . REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
- No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. RUN the on-demand self-test (required to clear certain DTCs). CORRECT any unresolved DTCs. CLEAR all DTCs. TEST the system for normal operation.