U1502

U1502-IMPLAUSIBLE MESSAGE DATA LENGTH RECEIVED FROM TCM

For a complete wiring diagram, refer to Diagrams/Electrical. Electrical Diagrams

- When Monitored:

Continuously with the ignition on.

- Set Condition:

When the Anti-Lock Brake Module detects an incorrect CAN message from the Transmission Control Module (TCM).





Diagnostic Test

1. CHECK IF FCM CAN BUS DTCS ARE PRESENT

With the scan tool, read FCM DTCs.

Are there any FCM CAN BUS DTCs present?

Yes

- Refer to applicable DTC test and diagnose the appropriate symptom.
- Perform ABS VERIFICATION TEST. ABS Verification Test

No

- Go To 2

2. CHECK IF TRANSMISSION DTCS ARE PRESENT

With the scan tool, read Transmission DTCs.

Are there any Transmission DTCs present?

Yes

- Refer to Computers and Control System and diagnose the appropriate symptom.
- Perform ABS VERIFICATION TEST. ABS Verification Test

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 ABS VERIFICATION TEST. ABS Verification Test