What it means
The total current draw of drive motor B reports a current fault. Motor operation may be impaired. 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 is an electric traction motor whose inverter supplies and regulates current for propulsion or regenerative braking. The control module monitors its total current and sets P0C02 when the reported current is faulty; an out-of-range calculation or drifting current sensor can cause the inverter to limit torque.
Common causes
Most likely first.
- Calculated current outside expected range
- Current sensor drift
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Read freeze-frame and live data for Drive Motor B current, requested torque, speed, and temperature, and note whether the fault appears during acceleration or regeneration.
- Check for other Drive Motor B, inverter, or position and temperature sensor codes that could affect the current calculation.
- With the vehicle powered down according to its service procedure, inspect Drive Motor B's high-voltage connectors and harness for damage, loose pins, or corrosion.
- Have a qualified technician compare the current reading with commanded motor operation using the manufacturer's diagnostic procedure and high-voltage precautions.
- Test the Drive Motor B current sensor and its wiring against the manufacturer's specification before condemning the motor or inverter.
Common fixes
- Clean or repair a confirmed poor connection in the Drive Motor B sensor or harness circuit.
- Repair damaged wiring or connector pins.
- Replace a current sensor confirmed to be drifting or faulty.
- Repair the inverter or motor only if testing identifies a fault there.
Can I keep driving?
Drive gently and avoid demanding acceleration or long climbs because the control system may cut Drive Motor B torque or enter limp mode. If propulsion becomes intermittent or the vehicle warns of shutdown, stop in a safe place.
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.