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Pinpoint Test B: An Individual Courtesy Lamp Is Inoperative




Interior Lighting

Pinpoint Tests

Pinpoint Test B: An Individual Courtesy Lamp Is Inoperative

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

Normal Operation

The Lighting Control Module (LCM) provides voltage to the courtesy lamps on circuit 53 (BK/LB). The courtesy lamps are grounded through circuit 57 (BK).

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Interior lamp



PINPOINT TEST B: AN INDIVIDUAL 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.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.

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B1 CHECK CIRCUIT 53 (BK/LB) FOR AN OPEN


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





- Is the voltage greater than 10 volts?

Yes
GO to B2.

No
REPAIR the circuit. TEST the system for normal operation.

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B2 CHECK CIRCUIT 57 (BK) FOR AN OPEN


- Disconnect: Negative Battery Cable.
- Measure the resistance between the inoperative courtesy lamp, harness side and ground as follows:





- Is the resistance less than 5 ohms?

Yes
INSTALL a new courtesy lamp assembly for the one in question. TEST the system for normal operation.

No
REPAIR the circuit. TEST the system for normal operation.

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