P280A: Transmission Range Sensor A Circuit Not Learned
What to do
Apply the parking brake every time you park, and treat the selector display with suspicion. The transmission has lost one of the two witnesses it uses to confirm which range it is in — check the car is truly holding before stepping away, and expect the occasional refused shift or reluctant start while it protects itself. Repair promptly; the second sensor is now the only one.
What this code means
The module has no learned baseline for transmission range sensor A.
"Not learned" means the module has no baseline for this sensor, not that anything is broken. Range sensors on shift-by-wire transmissions are calibrated in place: the module records what the sensor reads at each true detent — park here, drive there — and judges every future reading against that map. A new sensor, a replaced module, or an interrupted procedure leaves the map empty, and the module refuses to trust positions it never learned.
It almost always follows work: a sensor or module changed without the learn procedure, a battery disconnected mid-programming. The fix is the scan-tool learn routine, not another sensor — and a car that misbehaves right after gearbox electrical work has this written all over it.
Likely causes
Start here
- Actuator not calibrated after repair · moderate
- Gearbox actuator calibration lost · moderate
Less common
- Interrupted module programming · specialist
- Battery disconnected or module reprogrammed · easy
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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