OBD-II · Network and communication (U)
U0402
Invalid data received from transmission control module
What it means
A module is receiving messages from the gearbox control unit, but the data in them is missing, out of range or implausible.
Symptoms
- Gearbox warning or limp mode
- Gear display missing or wrong
- Engine or stability control warnings
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | a gearbox fault that makes its control unit send substitute values (read gearbox codes first) |
| 02 | low 12V battery voltage |
| 03 | incorrect coding or software after gearbox or control unit replacement |
| 04 | intermittent wiring fault |
What to check, step by step
- 01Read and fix gearbox control unit codes first
- 02Check 12V battery and charging voltage
- 03Check gearbox control unit software and coding after any replacement
- 04Check CAN wiring if the fault returns on its own