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Pinpoint Test X: An Individual Reversing Lamp Is Inoperative




Reversing Lamps

Pinpoint Tests


Pinpoint Test X: An Individual Reversing Lamp Is Inoperative

Refer to Wiring Diagram Set 93, Reversing Lamps for schematic and connector information. Diagrams By Number

When the Body Control Module B (BCM-B) receives a message from the PCM indicating the transmission is in reverse, the BCM-B supplies voltage to the reversing lamps.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Rear lamp jumper harness
- BCM-B



PINPOINT TEST X: AN INDIVIDUAL REVERSING 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.

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X1 CHECK FOR VOLTAGE TO THE REVERSING LAMP


- Ignition OFF.
- Disconnect: Inoperative Rear Lamp.
- Ignition ON.
- Apply the parking brake.
- Select REVERSE.
- Measure the voltage between the LH rear lamp C498-1, circuit CLS10 (GN/BN), harness side and ground; or between the RH rear lamp C499-1, circuit CLS11 (GY/VT), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
REPAIR or INSTALL a new rear lamp jumper harness. TEST the system for normal operation.

No
GO to X2.

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X2 CHECK THE REVERSING LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN


- Ignition OFF.
- Measure the resistance between the LH reversing lamp C498-1, circuit CLS10 (GN/BN), harness side and between the BCM-B
C4368a-5, circuit CLS10 (GN/BN), harness side: or between the RH reversing lamp C499-1, circuit CLS11 (GY/VT), harness side and between the BCM-B C4368a-17, circuit CLS11 (GY/VT), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to X3.

No
REPAIR circuit CLS10 (GN/BN) or CLS11 (GY/VT) for an open. TEST the system for normal operation.

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X3 CHECK FOR CORRECT BCM-B OPERATION


- Disconnect all the BCM-B connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the BCM-B 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 BCM-B. 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. CLEAR the DTCs. REPEAT the self-test.

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