P0CDBDrive Motor A Position Sensor Circuit C Range/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
- P0CDB flags circuit C of the drive motor A position sensor as present but implausible: its amplitude or phase, or the angle calculated from it, no longer agrees with the other circuits or with the observed motor speed. GM runs comparable tests on the main resolver signals, for example an amplitude check of the sine and cosine windings under P0A3F rated Type A, and limits for circuits A and B. No manufacturer publicly documents P0CDB itself, and none explains what circuit C carries; CARB requires rationality monitoring of electric drive inputs. Plausible causes are a resolver that has shifted on its mount, rotor bearing play, a winding or terminal whose values change with heat, or a controller calibration issue. Drivers usually see a hybrid warning and reduced electric power. Hard circuit faults are P0CDC and P0CDD.
- What you may notice
- Hybrid system warning, MIL
- Reduced electric power, engine starts in EV mode
- Fault appears more often when the drivetrain is warm
- Likely causes
- PossibleWinding or terminal of the resolver changing its values when hot
- PossibleResolver shifted on its mount or rotor bearing play
- RareMotor control module software or calibration
- 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: €150 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.