B1644
B1644-REAR LEFT TURN CONTROL CIRCUIT HIGH
For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.
- When Monitored:
Continuously
- Set Condition:
When the Front Control Module (FCM) detects a short to battery on the rear left turn signal circuit.
1. TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
2. Clear all FCM DTCs.
3. Turn the Left Turn Signal on.
4. With the scan tool, read DTCs.
Does the scan tool read: B1644-REAR LEFT TURN CONTROL CIRCUIT HIGH?
Yes
- Go To 2
No
- The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. (L63) LEFT REAR TURN SIGNAL CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the Right Tail Stop Turn Lamp harness connector.
3. Disconnect the 49 way FCM/IPM harness connector.
4. Measure the resistance of the (L63) Left Rear Turn Signal Control circuit.
Is the resistance above 5.0 Ohms?
No
- Repair the open (L63) Left Rear Turn Signal Control circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
Yes
- Go To 4
3. (L63) LEFT REAR TURN SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition on.
2. Measure the voltage on the (L63) Left Rear Turn Signal Control circuit at the Right Tail Stop Turn Lamp harness connector.
Is there any voltage present?
Yes
- Repair the short to voltage in the (L63) Left Rear Turn Signal Control circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 4
4. FRONT CONTROL MODULE (FCM)
1. Turn the ignition off.
2. Disconnect the Front Control Module from the IPM.
3. Measure the voltage between (L63) Left Rear Turn Signal Control circuit and ground in the IPM.
Is there any voltage present?
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.