51A1
51A1-IMPLAUSIBLE ENGINE TORQUE MESSAGE RECEIVED
For a complete wiring diagram, Refer to the Wiring Information Electrical Diagrams.
Theory of Operation
The messages sent on the CAN bus are distinguished by an identifier (ID). Each CAN ID is defined to contain a certain number of bytes. The Transmission Control Module (TCM) verifies that it has received the proper number of bytes for each ID.
- When Monitored:
Continuously with the ignition on, one valid CAN ID received at least once.
- Set Condition:
When the TCM detects an incorrect CAN ID from the ECM.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Transmission Pre-Diagnostic Troubleshooting Procedures.
1. CHECK FOR BCM CAN BUS DTCS
1. With the scan tool, read BCM DTCs.
Are there any BCM CAN BUS DTCs present?
Yes
- Perform the appropriate diagnostic procedure.Testing and Inspection
No
- Go To 2
2. CHECK IF ENGINE DTCS ARE PRESENT
1. With the scan tool, read engine DTCs.
Are there any engine DTCs present?
Yes
- Perform the appropriate diagnostic procedure.Testing and Inspection
No
- Using the schematics as a guide, check the Transmission Control Module (TCM) 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 TCM.
- Perform NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.