B1643

B1643-REAR LEFT TURN CONTROL CIRCUIT LOW







- When Monitored:
With the Turn Signal activated.

- Set Condition:
When the Front Control Module (FCM) detects a low condition on the (L63) Left Rear Turn Signal Control circuit.





1. INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, erase all FCM DTCs.
3. Turn the Left Turn Signals on.
4. With the scan tool, read DTCs.

Does the scan tool display: B1643-REAR LEFT TURN CONTROL CIRCUIT LOW?

Yes

- Go To 2

No

- The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK (L63) LEFT REAR TURN SIGNAL CONTROL CIRCUIT IN BODY HARNESS FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the IPM C2 harness connector.
3. Disconnect the Left Tail Stop/Turn Tail Lamp harness connector.
4. Measure the resistance of the (L63) Left Rear Turn Signal Control circuit between ground and the IPM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

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

No

- Go To 3

3. CHECK (L63) LEFT REAR TURN SIGNAL CONTROL CIRCUIT IN IPM FOR A SHORT TO GROUND




1. Disconnect the Front Control Module (FCM) from the IPM 49-way connector.
2. Reconnect the IPM C2 harness connector.
3. Measure the resistance of the (L63) Left Rear Turn Signal Control circuit between ground and the IPM 49-way connector.

Is the resistance below 5.0 Ohms?

Yes

- Replace the Integrated Power Module (IPM).
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Front Control Module (FCM).
- Perform the BODY VERIFICATION TEST. Body Verification Test.