P1631

P1631-TCM INTERNAL- PROCESSOR CLOCK PERFORMANCE





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

Theory of Operation

The Transmission Control Module (TCM) performs various internal tests to verify proper controller operation. This DTC indicates that there is an issue with the TCM's internal clock. If the TCM detects an error with the controllers internal clock, the controller will enter Limp-in mode and illuminate the MIL.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
If the TCM detects an error with the controllers internal clock.





Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.
TRANSMISSION CONTROL MODULE (TCM)

Repair

- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals 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 the NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.