What it means
The ECM detects a low fault on the drive motor b 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 inverter voltage sensor B supplies a voltage signal used to monitor the B motor inverter. This code sets when the signal is abnormally low, such as from a short to ground, an internally shorted sensor, or poor contact at a corroded connector.
Common causes
Most likely first.
- Signal wire shorted to ground
- Internal sensor short
- Connector pins corroded - high contact resistance
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 check sensor B live data to confirm the signal is low and determine whether the fault appears under particular operating conditions.
- With the vehicle safely powered down according to its hybrid or EV procedures, inspect the sensor B connector for corrosion, bent pins, or poor seating.
- Inspect the sensor B signal wire for damage or contact with ground, paying attention to areas near the inverter and connector.
- Test the signal circuit for a short to ground and check connector contact quality using the manufacturer's procedure.
- If the circuit and connector pass inspection, test Drive Motor B inverter voltage sensor B and replace it if it is internally shorted.
Common fixes
- Clean and properly reconnect corroded or loose sensor B connector terminals where serviceable.
- Repair a sensor B signal wire shorted to ground.
- Replace the Drive Motor B inverter voltage sensor B if it has an internal short.
- Replace damaged connector terminals that cannot maintain reliable contact.
Can I keep driving?
Limit driving because the vehicle may reduce motor torque or enter limp mode, and it may shut down. If power is limited or a shutdown warning appears, stop safely and arrange assistance.
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.