What it means
Electrical fault on the resolver or encoder used to determine rotor position of drive motor A. Position is essential for vector control commutation.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Drive Motor A's resolver or encoder measures rotor position so the inverter can align current with the motor's rotation. The control module compares that position signal with expected motor behavior and sets this code when the signal is outside the expected range or does not track correctly. A range or performance fault can come from the sensor, its wiring or shielding, or its mounting.
Common causes
Most likely first.
- Resolver failed
- Resolver wiring shielding fault
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Read freeze-frame data and live data for Drive Motor A rotor position, motor speed, and torque command to identify when the signal became implausible.
- Inspect the Drive Motor A resolver or encoder connector and harness for damage, poor seating, corrosion, or disturbed shielding.
- Check the resolver or encoder signal and wiring against the manufacturer's specifications, looking for an out-of-range signal or interference.
- Compare position feedback with motor speed and commanded torque during the manufacturer's approved diagnostic routine to identify tracking errors.
- If wiring and shielding pass, check sensor mounting and alignment and test the resolver or encoder using the manufacturer's procedure.
Common fixes
- Reseat the Drive Motor A position-sensor connector and secure its harness and shielding.
- Repair damaged or poorly shielded wiring in the resolver or encoder circuit.
- Correct sensor mounting or alignment if the manufacturer's procedure confirms it is out of position.
- Replace the Drive Motor A resolver or encoder if it fails testing.
Can I keep driving?
Limit driving and avoid high speeds or hard acceleration because incorrect Drive Motor A position feedback can cause sudden torque reduction or limp mode. Stop safely if the vehicle's power becomes unstable or a stop warning appears.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.