Pinpoint Test A: The Interior Lamp Is Inoperative

Interior Lighting

Pinpoint Test

Pinpoint Test A: The Interior Lamp Is Inoperative

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

Normal Operation

Voltage is supplied to the Smart Junction Box (SJB). The SJB fuse 13 (15A) supplies voltage to the interior lamp relay (internal to the SJB). When any door is opened, the door ajar switch closes, signaling the SJB. The SJB monitors the door ajar circuits and the instrument panel dimmer switch input. Based on these inputs, the SJB supplies voltage to the interior lamp.

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- Interior lamp
- SJB



PINPOINT TEST A: THE INTERIOR 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.

-------------------------------------------------
A1 CHECK FOR VOLTAGE TO THE INTERIOR LAMP


- Ignition ON.
- Disconnect: Interior Lamp C931.
- Open one of the doors.
- Measure the voltage between the interior lamp C931-1, circuit CLN28 (GN/BU), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
INSTALL a new interior lamp. TEST the system for normal operation.

No
VERIFY the SJB fuse 13 (15A) is OK. If OK, GO to A2. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number

-------------------------------------------------
A2 CHECK THE INTERIOR LAMP INPUT CIRCUIT FOR AN OPEN


- Ignition OFF.
- Disconnect: SJB C2280c.
- Measure the resistance between the interior lamp C931-1, circuit CLN28 (GN/BU), harness side and the SJB C2280c-8, circuit CLN28 (GN/BU), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to A3.

No
REPAIR circuit CLN28 (GN/BU) for an open. TEST the system for normal operation.

-------------------------------------------------
A3 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 Body Control Systems. 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.

-------------------------------------------------