What it means
The current sensor of the drive motor B reports a circuit fault. Current measurement is unreliable. The drive motor's position, current and temperature are watched continuously; a fault here downgrades the inverter to a safe operating point or triggers torque reduction.
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 current sensor measures electrical current so the inverter can control that motor's torque. The hybrid control system monitors the sensor circuit for a fault that makes its current reading unreliable. It may reduce motor torque or restrict inverter operation.
Common causes
Most likely first.
- Current sensor failed
- Wiring fault
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Use a scan tool to save freeze-frame data and compare Drive Motor B current readings with commanded torque and operating conditions.
- Check for related inverter or hybrid-system codes that could identify a shared supply, ground, or communication issue.
- With the high-voltage system made safe according to service information, inspect Drive Motor B's current-sensor connector and accessible wiring for damage, corrosion, or poor seating.
- Use the wiring diagram to check Drive Motor B's sensor power, ground, and signal circuits for opens, shorts, or poor connections against the manufacturer's specification.
- If the wiring is sound, test Drive Motor B's current sensor and compare its output with scan-tool data using the manufacturer's diagnostic procedure.
Common fixes
- Repair damaged wiring in Drive Motor B's current-sensor circuit.
- Clean, secure, or repair the current-sensor connector and terminals.
- Correct a failed sensor power or ground connection.
- Replace Drive Motor B's current sensor if testing confirms it has failed.
- Repair an inverter fault if its input or monitoring circuit is found to be the cause.
Can I keep driving?
Because motor torque may be reduced or the hybrid system may shut down, avoid long trips and situations that require dependable acceleration. Stop in a safe place if the vehicle loses power or displays a shutdown warning.
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.