U0401

U0401-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM

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

- When Monitored:
Continuously with the ignition on, one valid CAN message received at least once, and no U0002-CAN C Bus Off Performance DTC present.

- Set Condition:
When the Anti-Lock Brake Module detects an incorrect CAN message from the Engine Control Module (ECM).





1. CHECK FOR DTC U0401-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM

NOTE: This DTC must be active for the results of this test to be valid.

1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. Cycle the ignition switch from off to on.
4. With the scan tool, read DTCs.

Does the scan tool display: U0401-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM?

Yes

- Go To 2

No

- Perform the ABS INTERMITTENT CONDITION TEST. ABS Intermittent Condition Test.

2. CHECK IF FCM CAN BUS DTCS ARE PRESENT
1. With the scan tool, read FCM DTCs.

Are there any FCM CAN BUS DTCs present?

Yes

- Perform the appropriate diagnostic procedure Testing and Inspection.

No

- Go To 3

3. CHECK IF ENGINE DTCS ARE PRESENT
1. With the scan tool, read Engine DTCs.

Are there any Engine DTCs present?

Yes

- Testing and Inspection for diesel engine applications or Testing and Inspection for gas engine applications and perform the appropriate diagnostic procedure.

No

- Using the schematics as a guide, check the Anti-Lock Brake Module pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the Anti-Lock Brake Module.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.