Transmission Range Sensor A Circuit Not Learned
What it means
P280A means the transmission controller hasn't stored a valid calibration for range sensor "A" — the gear-position (PRNDL) input. It typically appears after the sensor or controller is replaced and the required relearn procedure hasn't been run, so the module can't reliably map the signal to Park, Reverse, Neutral, and Drive. Until it's learned, the car may not start, may show the wrong gear, or may shift harshly. The fix is the calibration procedure, not just clearing the code.
Can I keep driving? Sometimes — until the range sensor is learned, the controller may not recognize gear positions, causing no-start, wrong-gear indication, or harsh shifts.
Common symptoms
What you'll notice
- Check-engine light on
- Gear position display wrong or not recognized
- No-crank in Park, or the engine won't start
- Harsh or delayed shifts until the sensor is calibrated
Common causes
Most likely first
- Range sensor or transmission controller replaced without running the relearn/calibration procedureLikely
- Shift linkage or sensor misaligned so the learned positions don't matchCommon
- Poor connector contact or intermittent wiring interrupting the learnCommon
- Faulty transmission range sensor that can't be calibratedLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm whether a sensor or controller was recently replaced.
- Verify shift-linkage adjustment and that the sensor is aligned to the Park reference.
- Perform the manufacturer's transmission range sensor relearn/calibration procedure with a capable scan tool.
- Inspect the connector and wiring for intermittent contact that could abort the learn.
- If it still won't learn, replace the range sensor and repeat the procedure.
FAQ
Quick answers
Is it safe to drive with P280A?+
Can I just clear P280A?+
Related codes
Often seen with P280A
Read & clear P280A yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.