P0861Gear Shift Control Module A Communication Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Gear shift control modules A and B are selector modules of shift-by-wire systems, such as Audi's selector lever J587 or Stellantis' rotary shift module. The codes cover a dedicated link to the gearbox module and the module's plausibility. If the selected range cannot be transferred reliably, the gearbox holds its range, goes to P at standstill or into limp mode. Modules on CAN report lost communication as U0103 or invalid data as U0404 instead; GM uses its own codes. P0861 means the link to module A stays at a low level, typically a short to ground or a sender that no longer releases the line. No maker documents it.
- What you may notice
- Selector or gearbox warning in the instrument cluster
- Range cannot be selected or only with delay, car stays in P/N
- Gearbox limp mode
- Likely causes
- LikelyCommunication line shorted to ground
- PossiblePower or ground of the selector module
- PossibleSoftware of selector or gearbox module
- PossibleSelector module faulty
- 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: €100 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.