What it means
The hybrid electronics coolant pump A reports a control circuit low 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
Electronics coolant pump A circulates coolant to cool hybrid or EV power electronics, and its control circuit operates the pump. P0CEB sets when the monitored control circuit voltage is lower than expected, which can indicate a short to ground, a motor short, or a poor connection.
Common causes
Most likely first.
- Wire shorted to ground
- Internal motor short
- Connector pins corroded - high contact resistance
Symptoms
- Hybrid or EV system warning light on
- Reduced power or limited vehicle operation
- Cooling-system warning may appear
How to diagnose it
- Check freeze-frame data and scan-tool pump A command and cooling status to see when the low circuit condition is detected.
- With the vehicle powered down under the manufacturer's high-voltage safety procedure, inspect pump A's connector and terminals for corrosion, damage, or loose contact.
- Inspect the pump control harness for a wire shorted to ground or insulation rubbed through against the body.
- Measure the control circuit and pump motor using the manufacturer's wiring diagram and electrical specifications.
- If the wiring and connector are sound, test pump A operation and the control output according to the manufacturer's procedure.
Common fixes
- Clean and secure corroded or loose pump connector terminals.
- Repair a control wire shorted to ground or damaged insulation.
- Replace pump A if testing confirms an internal motor short.
- Repair a faulty control-side connection identified by circuit testing.
Can I keep driving?
Avoid driving under heavy load if power is reduced or a cooling warning appears, as pump A may not provide dependable cooling to the power electronics. Stop safely if the warning persists or the vehicle enters limited operation.
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.