What it means
The motor electronics coolant pump C (cooling the drive inverter or motor) reports a control circuit high 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 circulates coolant through the motor electronics, such as the drive inverter or motor. The control module monitors Pump C’s electrical control circuit and sets P2BD6 when it detects a voltage higher than expected, which can happen if the control wire is shorted to battery power or the pump circuit is open.
Common causes
Most likely first.
- Control wire shorted to B+
- Open pump motor
- Connector pins corroded - high contact resistance
Symptoms
- Hybrid-system warning light or message
- Reduced power
- Power electronics overheating warning
How to diagnose it
- Read freeze-frame data and hybrid-system codes to see when the Pump C circuit fault occurred and whether overheating or reduced-power faults were logged at the same time.
- With the vehicle safely powered down as specified by the manufacturer, inspect Pump C’s connector and harness for corrosion, loose pins, or damage that could expose the control wire to battery power.
- Check the scan-tool data for Pump C command and status, if available, and compare them with the symptoms to see whether the pump responds to commands.
- Test the Pump C control wire for a short to B+ and check circuit continuity using the manufacturer's wiring diagram and specifications.
- If the wiring and connector are sound, test Pump C’s motor circuit for an open and verify the pump operates as specified before replacing it.
Common fixes
- Clean and secure corroded or loose Pump C connector pins, or repair the connector.
- Repair the control wire where it is shorted to B+ or damaged.
- Replace Pump C if its motor circuit is open or it fails the specified operation test.
Can I keep driving?
Avoid driving if a power electronics overheating warning appears or power is reduced; continued use can overheat and damage the inverter or motor electronics. If no warning is present, limit driving and arrange prompt diagnosis, since the system may enter reduced-power mode.
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.