Check for accompanying codes like P1626 (missing message from TCM) or ABS/TC-related codes.
Data Bus Powertrain – Malfunction / No Communication. p1648-vw
Repairing broken CAN bus wires.
Pull up the passenger-side carpet/sill panel, open the TCM plastic box, and look for water, condensation, or green corrosion on the pins. Check for accompanying codes like P1626 (missing message
Automatic transmission stuck in a single gear or "limp mode" (shifting harshly). ABS/Traction Control lights on the dashboard. Slow acceleration or poor takeoff performance. Unexplained "no start" conditions. 3. Diagnostic & Troubleshooting Steps open the TCM plastic box
This is a communication error between ECUs, not necessarily a failed sensor. 1. Common Causes