Pinpoint Test W: The Individual Reversing Lamp Is Inoperative

Reversing Lamps

Pinpoint Tests

Pinpoint Test W: The Individual Reversing Lamp Is Inoperative

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

Normal Operation

When the reversing lamps relay is energized, voltage is routed to the reversing lamps.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Bulb holder (vehicles with pickup bed)
- Rear lamp assembly (vehicles without pickup bed)



PINPOINT TEST W: THE 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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W1 CHECK FOR VOLTAGE TO THE REVERSING LAMP


- Ignition OFF.
- Apply the parking brake.
- Disconnect: Inoperative Reversing Lamp.
- Ignition ON.
- Select REVERSE.
- For vehicles with a pickup bed, measure the resistance between the LH reversing lamp C451-1, circuit CLS10 (GN/BN), harness side and ground; or between the RH reversing lamp C461-1, circuit CLS10 (GN/BN), harness side and ground.




- For vehicles without a pickup bed, measure the resistance between the LH reversing lamp C423-1, circuit GD176 (BK/WH), harness side and ground; or between the RH reversing lamp C422-1, circuit GD176 (BK/WH), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to W2.

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

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W2 CHECK FOR VOLTAGE TO THE REVERSING LAMP USING THE CONNECTOR GROUND


- For vehicles with a pickup bed, measure the voltage between the LH reversing lamp C451-1, circuit CLS10 (GN/BN), harness side and the LH reversing lamp C451-2, circuit GD176 (BK/WH), harness side; or between the RH reversing lamp C461-1, circuit CLS10 (GN/BN), harness side and the RH reversing lamp C461-2, circuit GD176 (BK/WH), harness side.




- For vehicles without a pickup bed, measure the voltage between the LH reversing lamp C423-1, circuit CLS10 (GN/BN), harness side and the LH reversing lamp C423-2, circuit GD176 (BK/WH), harness side; or between the RH reversing lamp C422-1, circuit CLS10 (GN/BN), harness side and the RH reversing lamp C422-2, circuit GD176 (BK/WH), harness side.




- Is the voltage greater than 10 volts?

Yes
INSTALL a new bulb holder (vehicles with a pickup bed) or rear lamp assembly (vehicles without a pickup bed). TEST the system for normal operation.

No
REPAIR circuit GD176 (BK/WH) for an open. TEST the system for normal operation.

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