Diagnostic Test
- 1) TEST FOR INTERMITTENT CONDITION
Turn the ignition on.
NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.With the scan tool, select ECU view.
NOTE: A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.NOTE: Check the FCM for any active CAN C hardware and any ignition related DTCs, perform DTCs before proceeding.Does the scan tool display a red X next to the module?
Yes
- Go to step 2).
No
- The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
- 2) CHECK ECM POWER AND GROUND
Check the ECM power and ground circuits.
Were any problems found?
Yes
- Repair as necessary.
- Perform ECM VERIFICATION TEST.
No
- Go to step 3).
- 3) (D65) CAN C BUS (+) CIRCUIT OPEN
Turn the ignition off.
Disconnect the FCM C1 harness connector.
Disconnect the ECM C2 harness connector.
Measure the resistance of the (D65) CAN C Bus (+) circuit between the FCM connector and the ECM connector.
Is resistance below 5.0 ohms?
Yes
- Go to step 4).
No
- Repair the (D65) CAN C Bus (+) circuit for an open.
- Perform ECM VERIFICATION TEST.
- 4) (D64) CAN C BUS (-) CIRCUIT OPEN
Measure the resistance of the (D64) CAN C Bus (-) circuit between the FCM connector and the ECM connector.
Is resistance below 5.0 ohms?
Yes
- Replace and program the Engine Control Module in accordance with the service information.
- Perform ECM VERIFICATION TEST.
No
- Repair the (D64) CAN C Bus (-) circuit for an open.
- Perform ECM VERIFICATION TEST.