FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Pinpoint Test C: One Or More Interior Courtesy Lamp Is Inoperative




Interior Lighting

Pinpoint Test C: One Or More Interior Courtesy Lamp Is Inoperative

Refer to Wiring Diagram Set 89, Interior Lamps for schematic and connector information. Diagrams By Number

Normal Operation

The Smart Junction Box (SJB) fuse 9 (15A) supplies power for the interior courtesy lamps. When the SJB (Smart Junction Box) receives the required input (such as an open door or request from the instrument panel dimmer switch), the SJB (Smart Junction Box) provides voltage to the interior courtesy lamps.





This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- Interior lamp

- SJB (Smart Junction Box)

PINPOINT TEST C : ONE OR MORE INTERIOR COURTESY LAMP IS INOPERATIVE

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

C1 CHECK THE OPERATION OF ALL THE INTERIOR COURTESY LAMPS

- Ignition OFF.

- Press and hold the instrument panel dimmer switch to the DOME LAMP ON (second detent up) position for 3 seconds.

Are all the interior courtesy lamps inoperative?

Yes
VERIFY the SJB (Smart Junction Box) fuse 9 (15A) is OK. If OK, GO to C4.

If not OK, Refer to the Wiring Diagrams to identify the possible causes of the circuit short. After the repair: Diagrams By Number

If no DTCs are present, TEST the system for normal operation.

If DTC B106E is present, CLEAR the DTCs and REPEAT the self-test (required to enable the interior courtesy lamp output driver if DTC B106E is present). TEST the system for normal operation.

If DTC B106F is present, INSTALL a new SJB (Smart Junction Box). TEST the system for normal operation.

No
GO to C2.

C2 CHECK FOR VOLTAGE TO THE INTERIOR LAMP

- Turn the interior courtesy lamps off.

- Disconnect: Inoperative Lamp.

- Press and hold the instrument panel dimmer switch to the DOME LAMP ON (second detent up) position for 3 seconds.

- Measure the voltage between the inoperative lamp, harness side and ground as follows:









Is the voltage greater than 10 volts?

Yes
GO to C3.

No
REPAIR circuit VLN33 (GY/VT) for an open. TEST the system for normal operation.

C3 CHECK THE INTERIOR LAMP GROUND CIRCUIT FOR AN OPEN

- Measure the voltage between the inoperative interior lamp connector, harness side as follows:









Is the voltage greater than 10 volts?

Yes
INSTALL a new interior lamp for the lamp in question. REFER to Interior Lamp . TEST the system for normal operation.

No
REPAIR the ground circuit in question for an open. TEST the system for normal operation.

C4 BYPASS THE SJB (Smart Junction Box)

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) C2280A.

- NOTE: If the jumper wire fails, Refer to the Wiring Diagrams to identify the possible causes of the circuit short. After the repair: Diagrams By Number

If no DTCs are present, test the system for normal operation.

If DTC B106E is present, clear the DTCsand repeat the self-test(required to enable the courtesy lamp output driver if DTC B106E is present). Test the system for normal operation.

If DTC B106F is present, install a new SJB (Smart Junction Box). Test the system for normal operation.

Connect a fused jumper wire between the SJB (Smart Junction Box) C2280A-9, circuit VLN33 (GY/VT), harness side and battery positive.






Do the courtesy lamps illuminate?

Yes
REMOVE the jumper wire. GO to C5.

No
REMOVE the jumper wire. REPAIR circuit VLN33 (GY/VT) for an open. CLEAR the DTCs. REPEAT the self-test.

C5 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION

- Disconnect all the SJB (Smart Junction Box) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the SJB (Smart Junction Box) 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 (Smart Junction Box). 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.