What it means
The drive motor A inverter voltage sensors A and B do not correlate within the calibrated tolerance.
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 inverter voltage sensors A and B monitor the inverter voltage so the hybrid or electric drive control system can check its readings for consistency. This code sets when the two sensor readings disagree beyond the calibrated tolerance, which can result from sensor offset drift or a difference in their ground references.
Common causes
Most likely first.
- One sensor offset drifted
- Ground offset between sensors
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Save freeze-frame data and review live readings from inverter voltage sensors A and B, checking when and how far they diverge.
- Inspect the drive motor A inverter sensor connectors and accessible wiring for damage, corrosion, or loose grounds.
- Check the sensors' shared and individual ground paths for offset or poor connections using the manufacturer's diagnostic information.
- Compare both sensor outputs using the manufacturer's test procedure and specification, taking appropriate high-voltage precautions.
- If wiring and grounds pass, isolate and test the sensor readings individually, replacing the sensor confirmed to be out of calibration.
Common fixes
- Repair a loose or corroded sensor ground connection.
- Repair damaged wiring or connector terminals for the drive motor A inverter voltage sensors.
- Replace the voltage sensor confirmed to have offset drift.
- Clear the code and confirm sensors A and B correlate under the manufacturer's verification procedure.
Can I keep driving?
A hybrid or EV may reduce motor torque, enter limp mode, or shut down, so do not rely on it for a journey if the warning is active or power is reduced. Avoid working on inverter wiring; have the high-voltage system diagnosed using the manufacturer's safety procedures.
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.