P0A1CDrive Motor B Control Module Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0A1C is the counterpart of P0A1B for the second electric machine, drive motor B, and reports that its control processor is no longer trustworthy. GM hybrid tables use it for the motor control processor B: in 2016 calibrations the code sets when an inhibit path test at power-down fails three or more times, in 2011 calibrations internal processor integrity faults such as SPI, RAM or cache errors are counted. Both are Type A with MIL on the first trip. The code concerns the control electronics, not a phase current sensor; those faults use their own codes. Expect a hybrid warning and loss of the affected motor function.
- What you may notice
- Hybrid warning and MIL
- Reduced drive power or no electric drive
- Likely causes
- LikelyInternal processor or memory fault on the motor B control board
- PossibleCalibration or software fault in the inverter
- RareUnstable 12 V supply or ground to the inverter electronics
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €5,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.