Final Drive Control Module (FDCM)

U0100-LOST COMMUNICATION WITH ECM/PCM

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

- When Monitored:
With the ignition on

Battery voltage between 10 and 16 volts

IOD fuse installed

TIPM is configured correctly

- Set Condition:
Bus messages not received from the ECM/PCM for approximately two to five seconds.





1. VERIFY DTC IS ACTIVE

NOTE: Make sure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.

1. Ignition on, engine not running.
2. With the scan tool, read DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Go To 5

2. CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS
1. With the scan tool, read all active DTCs from all modules.
2. Check for:
- TIPM configuration.
- CAN B or C hardware electrical.
- VIN Missing/Mismatch.
- Battery or ignition related DTCs.

Does the scan tool display any active DTCs to the conditions listed above?

Yes

- Perform the appropriate diagnostic procedures, Testing and Inspection.

No

- Go To 3

3. VERIFY THAT THE ECM/PCM IS ACTIVE ON THE BUS
1. Ignition on, engine not running.
2. With the scan tool, select Network Diagnostics.
3. Verify that the PCM is active on the bus.

Is the PCM active on the bus?

Yes

- Go To 4

No

- Perform the appropriate diagnostic procedure, Testing and Inspection.

4. CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
1. With the scan tool, select Network Diagnostics.

Is there more than one module with active DTCs "Logged Against" the PCM?

Yes

- Replace the Powertrain Control Module (PCM).
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace the module that set this DTC.
- Perform the FDCM VERIFICATION TEST. FDCM Verification Test.

5. INTERMITTENT WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle test the wiring harness and connectors while checking for shorted and open circuits.
4. Using the scan tool, monitor the data related to this circuit while performing the wiggle test. Look for the data to change or for the DTC to reset.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the FDCM VERIFICATION TEST. FDCM Verification Test.

No

- Test complete.