What it means
The total current draw of drive motor B reports a current high fault. Motor operation may be impaired.
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 powered by an inverter that controls current through its three motor phases. The control module sets P0C04 when total current for Drive Motor B is higher than expected, which can happen under overload or when motor phases are shorted together.
Common causes
Most likely first.
- Motor overload
- Short between motor phases
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Review freeze-frame and live hybrid data for Drive Motor B current, requested torque, speed, and temperature to identify when the excess current occurs.
- Check for related inverter, motor, or cooling-system codes that could indicate a load or temperature problem.
- With the vehicle powered down according to the manufacturer's procedure, inspect Drive Motor B's high-voltage harness and connectors for damage or heat discoloration.
- Have a qualified technician test the motor phases for a short and inspect the inverter using the manufacturer's high-voltage isolation procedure.
- Compare current-sensor readings with commanded output and the manufacturer's specification to rule out a false high reading.
Common fixes
- Repair damaged or overheated Drive Motor B wiring or connectors.
- Correct a confirmed operating or mechanical condition that is overloading the motor.
- Repair or replace the motor or inverter component confirmed to have a phase short.
- Replace a current sensor only if testing shows it is reporting incorrectly.
Can I keep driving?
Avoid hard acceleration, towing, and steep climbs because excessive Drive Motor B current can trigger torque reduction or shutdown. If power drops suddenly or a hybrid warning escalates, pull over safely.
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.