What it means
The HV battery pack coolant pump A reports a control circuit low condition. Battery thermal management may be impaired.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Battery-pack coolant pump A circulates coolant through the battery cooling system, and its control circuit switches or regulates pump operation. The module sets P0C48 when it detects a low electrical condition on that control circuit, which may indicate a short to ground or a fault in the pump or driver.
Common causes
Most likely first.
- Short to ground in the pump control circuit
- Faulty coolant pump or driver
- Poor connector connection
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
How to diagnose it
- Save freeze-frame data and check related codes, then use live data or a supported scan-tool command to compare the requested operation of pump A with its reported status.
- With the vehicle powered down as specified by the manufacturer, inspect pump A's connector and control wiring for corrosion, loose terminals, or insulation rubbed through to ground.
- Check the control circuit for a short to ground using the manufacturer's wiring diagram and test procedure.
- Inspect the pump connector and driver connections for poor contact that could pull the control signal low.
- If the wiring is not shorted to ground, test pump A and its driver against the manufacturer's specification to identify which is pulling the circuit low.
Common fixes
- Reconnect or secure a loose pump A connector.
- Repair control wiring shorted to ground.
- Clean or replace corroded or damaged connector terminals.
- Replace pump A or its driver only if testing identifies it as the cause.
Can I keep driving?
Limit driving and avoid high loads or charging because pump A may not provide adequate battery cooling. Stop if power is reduced or a battery-temperature warning appears, and have the fault checked 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.