What it means
The motor electronics coolant pump C (cooling the drive inverter or motor) reports a control performance condition. Power electronics cooling may be impaired.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Pump C moves coolant through the motor electronics cooling loop, including the drive inverter or motor. The control module checks whether the pump’s cooling performance matches operating conditions and sets P2BD7 when circulation is inadequate, even if the electrical control circuit is not reporting a high-voltage fault.
Common causes
Most likely first.
- Pump output degraded with age
- Air pocket in coolant loop
Symptoms
- Hybrid-system warning light or message
- Reduced power
- Power electronics overheating warning
How to diagnose it
- Check freeze-frame data and hybrid-system codes for the conditions when Pump C performance was judged inadequate, including any power electronics temperature warnings.
- Inspect the Pump C coolant loop for visible leaks, low coolant, kinked hoses, or signs that air may be trapped.
- Use scan-tool data, where available, to compare Pump C command and status with motor electronics coolant temperatures and look for poor cooling response.
- Check that Pump C runs and that coolant circulates through its loop, following the manufacturer's safety and service procedures.
- If the loop is full and free of restrictions, test Pump C’s output against the manufacturer's specification and replace it if degraded.
Common fixes
- Bleed trapped air from the motor electronics coolant loop using the manufacturer's procedure.
- Correct low coolant or repair a leak in the Pump C loop, then refill and bleed as specified.
- Replace Pump C if its output is below the manufacturer's specification.
Can I keep driving?
Do not continue driving if the power electronics overheating warning appears or the vehicle limits power; inadequate circulation can overheat and damage the inverter or motor electronics. If there are no warnings, keep trips short and seek diagnosis promptly.
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.