What it means
The ECM detects a range/performance fault on the drive motor a inverter voltage sensor b circuit. Reading cannot be used reliably for control.
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 sensor B reports an inverter voltage used to control motor operation. This code sets when that signal is intermittent or erratic, changing unpredictably or dropping out rather than remaining a reliable measurement.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced
- Sensor element aged beyond calibration window
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Capture freeze-frame data and monitor live sensor B voltage while checking whether the fault coincides with vibration, reduced torque, or a warning.
- With the high-voltage system made safe, inspect sensor B's connector for incomplete seating, corrosion, or terminals that may lose contact as the vehicle moves.
- Inspect drive motor A inverter sensor B wiring for damage or a loose ground reference, and check for movement-related breaks.
- Use the manufacturer's specified test to monitor continuity and signal stability while gently checking accessible wiring and connectors for intermittent contact.
- If the circuit remains stable, test sensor B and its mounting for a shifting or aged element that produces an erratic signal.
Common fixes
- Fully seat and secure the sensor B connector.
- Clean or repair connector terminals with intermittent contact.
- Repair damaged wiring or a noisy ground reference in the sensor B circuit.
- Secure or replace sensor B if its mounting has shifted or its signal remains erratic.
Can I keep driving?
An intermittent signal can cause reduced torque, limp operation, or an unexpected loss of drive, so avoid trips where a shutdown would be hazardous. Stop driving if power cuts out or the vehicle warns of a hybrid system fault, and have the high-voltage system checked safely.
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.