B1646-11

B1646-11-REAR RIGHT TURN LAMP CONTROL - CIRCUIT SHORT TO GROUND





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

Theory of Operation

The Body Control Module (BCM) receives a communication network message from the Steering Column Control Module (SCCM) requesting turn signal lamp illumination. When this bus message is received, the BCM provides a pulsed voltage output through the rear turn signal control circuit. The rear turn signal control circuit connects to Turn Signal Light Emitting Diodes (LED) in the Lamp, Tail Stop Turn. The ground circuit connects through the vehicle harness to a body ground. For additional information on the Turn Signal Lamps operation, Exterior Lamps - Operation.

- When Monitored:
With the turn signal active.

- Set Condition:
When the Body Control Module (BCM) detects a low condition on the (L62) Right Rear Turn Signal Driver circuit.





1. INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, clear all DTCs.
3. Turn the Right Turn Signal on.
4. With the scan tool, read DTCs.

Does the scan tool display DTC: B1646-11-REAR RIGHT TURN LAMP CONTROL - CIRCUIT SHORT TO GROUND?

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. ATTEMPT TO SET THE OPPOSITE DTC
1. Turn the Right Turn Signal off.
2. Turn the ignition off.
3. Disconnect the Right Tail Lamp Assembly C1 harness connector.
4. Turn the ignition on.
5. Turn the Right Turn Signal on.
6. With the scan tool, read DTCs.

Does the scan tool display DTC: B1646-15-REAR RIGHT TURN LAMP CONTROL - CIRCUIT SHORT TO BATTERY OR OPEN?

Yes

- Replace the Right Rear Turn Signal Lamp. Tail Stop Turn Lamp - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. CHECK THE (L62) RIGHT REAR TURN SIGNAL DRIVER CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM F harness connector.
3. Measure the resistance between ground and the (L62) Right Rear Turn Signal 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 (L62) Right Rear Turn Signal Driver circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.