P0631VIN Not Programmed or Incompatible TCM
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P0631 is the transmission module counterpart of P0630: the transmission control module holds no VIN, an invalid one, or one that does not match the vehicle – usually compared with the VIN of the engine or body module. Typical is a replaced transmission module or mechatronic unit (on dual-clutch and automatic gearboxes with integrated control) that was not VIN-programmed, or a used part. Depending on the architecture the transmission module itself or the engine module sets the code. No manufacturer table or bulletin available to us names P0631; the description follows CARB's VIN rules and the documented P0630 procedure (Hyundai, Ford), where the VIN is distributed to all modules that need it and stored once. Shifting is usually normal, but adaptations or configuration may be blocked.
- What you may notice
- Check engine light or transmission warning
- Scan tool shows no or a wrong VIN in the transmission module
- Transmission adaptation possibly impossible
- Driving often normal
- Likely causes
- LikelyTransmission module or mechatronic unit replaced, VIN not written
- PossibleUsed transmission module from another vehicle
- PossibleInterrupted transmission module programming
- RareCAN communication fault during the VIN comparison
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.