B1007-19

B1007-19-LEFT TURN LAMP - OVER CURRENT

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

Theory of Operation

The Body Control Module (BCM) receives an input from the Left Multi-function Switch requesting turn signal lamp illumination. When this message is received, the BCM provides a pulsed voltage output through the Front and Rear Turn Signal Driver circuit. The Turn Signal Driver circuits connect to the single filament Turn Signal Lamps. 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 Left Turn Signal Driver circuit.





1. CHECK FOR AN ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. With the scan tool, read DTCs.

Does the scan tool display this DTC 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 FOR AN ACTIVE DTC WITH THE LEFT FRONT PARK/TURN LAMP HARNESS CONNECTOR DISCONNECTED
1. Turn the ignition off.
2. Disconnect the Left Front Park/Turn Lamp harness connector.
3. Turn the ignition on.
4. Turn the Left Turn Signal on.
5. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 3

No

- Replace the Left Front Turn Signal Bulb. Turn Signal Bulb - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK FOR AN ACTIVE DTC WITH THE LEFT REAR PARK/TURN LAMP HARNESS CONNECTOR DISCONNECTED
1. Turn the ignition off.
2. Disconnect the Left Rear Park/Turn Lamp harness connector.
3. Turn the ignition on.
4. Turn the Left Turn Signal on.
5. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 4

No

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

4. CHECK THE (L61) LEFT FRONT TURN SIGNAL DRIVER CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM C1 harness connector.
3. Measure the resistance between ground and the (L61) Left Front Turn Signal Driver circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the short to ground in the (L61) Left Front Turn Signal Driver circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. CHECK THE (L63) LEFT REAR TURN SIGNAL DRIVER CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM C2 harness connector.
3. Measure the resistance between ground and the (L63) Left Rear Turn Signal Driver circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the short to ground in the (L63) Left Rear Turn Signal Driver circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

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