What it means
The voltage sensor B circuit signal for drive motor A's inverter is lower than expected. The module sets this code when it detects low voltage in the monitored sensor circuit.
How it works
Drive motor A's inverter voltage sensor B measures an inverter voltage used by the control module to manage motor operation. This code sets when the sensor B circuit signal falls below the expected level, which can make the module limit or disable functions that depend on that reading.
Common causes
Most likely first.
- Short to ground in sensor wiring
- Failed voltage sensor
- Poor connector contact
- Inverter reference or ground fault
Symptoms
- Hybrid or EV warning light
- Reduced power
- Vehicle may not enter READY mode
- Reduced or unavailable regenerative braking
How to diagnose it
- Use a scan tool to capture freeze-frame data and live sensor B voltage, noting whether the low reading coincides with reduced power or a failure to enter READY.
- With the high-voltage system made safe, inspect drive motor A inverter sensor B wiring for a short to ground, pinched insulation, or damage near connectors.
- Check the sensor B connector for poor contact, corrosion, or a loose terminal that could pull the signal low.
- Test the circuit for a short to ground and verify its reference and ground as specified by the manufacturer.
- If the wiring and connector pass, test sensor B and the inverter reference or ground circuits to find whether the low signal originates inside the sensor or inverter.
Common fixes
- Repair sensor B wiring that is shorted to ground.
- Clean, reseat, or repair poor contacts at the sensor B connector.
- Replace drive motor A inverter voltage sensor B if it produces a low signal despite a sound circuit.
- Repair the inverter reference or ground fault if testing locates it there.
Can I keep driving?
The vehicle may have reduced power, lose regenerative braking, or fail to enter READY. Do not continue driving if power is limited or the vehicle cannot enter READY; the inverter contains hazardous high-voltage circuits.
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.