What it means
The ECM detects a intermittent/erratic 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 B's inverter voltage sensor B reports a voltage used by the module to manage that motor's inverter. This code sets when the signal is below the expected level; the supplied meaning instead describes an intermittent fault on motor A's sensor B circuit, so confirm the affected circuit and condition from the vehicle's diagnostic data.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Record freeze-frame data and live readings, verifying whether the low signal belongs to drive motor B inverter sensor B or an intermittent motor A sensor B circuit.
- With the high-voltage system made safe, inspect drive motor B sensor B's connector for incomplete seating, corrosion, or damaged terminals.
- Inspect the sensor B signal wire for a short to ground, and check its ground and reference connections for a poor contact.
- Test the circuit for shorts, continuity, and intermittent contact according to the wiring diagram and manufacturer's specification.
- If the wiring is sound, test sensor B and the inverter to determine whether the low or unstable reading comes from a failed sensor or internal inverter fault.
Common fixes
- Reseat and secure the drive motor B sensor B connector.
- Clean or repair corroded terminals or an intermittent ground contact.
- Repair a signal wire shorted to ground or otherwise damaged.
- Replace drive motor B inverter voltage sensor B if it fails the specified circuit test.
Can I keep driving?
Reduced power, limp operation, or failure to enter READY can leave the vehicle unable to move reliably. Avoid driving if the warning is paired with restricted or erratic power, and treat inverter wiring as hazardous high voltage.
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.