B1751

B1751-11-COURTESY LAMP CONTROL - CIRCUIT SHORT TO GROUND





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Body Control Module (BCM) provides a battery voltage output to certain lamps through the courtesy lamp circuit. These lamps use a dedicated path to ground for illumination. The same lamp may also use a reading lamp circuit, which uses a switched path to ground for illumination.

- When Monitored:
With the Courtesy Lamps Driver commanded on.

- Set Condition:
When the Body Control Module (BCM) detects a short to ground on the (M11) Courtesy Lamps Driver circuit for more than two seconds.





1. CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. Actuate the Courtesy Lamps.
3. With the scan tool, read DTCs.

Does the scan tool display DTC: B1751-11-COURTESY LAMP CONTROL - CIRCUIT SHORT TO GROUND as active?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK EACH LAMP ON THE (M11) COURTESY LAMPS DRIVER CIRCUIT FOR A SHORT TO GROUND

NOTE: Using the wiring diagram as a guide, disconnect each component on the circuit one at a time and check for an active DTC.

1. Turn the ignition off.
2. Disconnect one of the lamps on the circuit.
3. Turn the ignition on.
4. With the scan tool, read DTCs.

Does the scan tool display DTC: B1751-11-COURTESY LAMP CONTROL - CIRCUIT SHORT TO GROUND as active?

Yes

- Repeat this step for all the lamps on the circuit. Once all the lamps are disconnected: Go To 3

No

- Replace the bulb or lamp causing the short to ground condition. Courtesy Lamp - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (M11) COURTESY LAMPS DRIVER CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the BCM G harness connector.
3. Measure the resistance between ground and the (M11) Courtesy Lamps Driver circuit.

Is the resistance above 10K Ohms?

Yes

- Replace the BCM. Body Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the short to ground in the (M11) Courtesy Lamps Driver circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.