P0CE0

What it means

P0CE0 is a generic powertrain code meaning the control unit has judged that Hybrid/EV Battery Pack Coolant Control Valve A is not performing as commanded and appears stuck in the off (closed) position. The battery management or thermal management controller commanded the valve open, but coolant flow or temperature behaviour, or valve position feedback, did not match what it expected. The exact valve location, its function and the detection method depend on the make and model.

Symptoms

• Hybrid/EV system warning light or malfunction indicator on
• Reduced power or limited performance (derating) when the battery is hot
• Battery temperature higher than normal, or cooling fan and pump running harder or for longer than usual
• Reduced charging speed or regenerative braking
• Reduced EV range or the engine running more often on a hybrid
• Message on the dash about a battery or hybrid system fault

Possible causes

• Coolant control valve mechanically stuck or seized closed, or its actuator failedlikely
• Wiring or connector fault to the valve (corrosion, chafing, loose pin, open or short circuit)likely
• Low coolant level or air in the battery cooling circuit reducing flowpossible
• Blocked cooling circuit, kinked hose or restricted chiller or plate heat exchangerpossible
• Faulty battery coolant pump or a coolant temperature sensor giving incorrect readings that make the valve seem unresponsivepossible
• Fault in the thermal management or battery control unit, or an outdated software calibration where the manufacturer has issued an updaterare

How to diagnose

1. Read all stored and pending codes and freeze frame data, noting battery temperatures, coolant temperatures and vehicle state when the code set
2. Check for related codes covering the battery coolant pump, temperature sensors or other valves, and deal with those first
3. Follow the manufacturer's high-voltage safety procedure before touching any orange cable or battery component, and only let suitably trained staff work on the high-voltage system
4. Check the battery coolant level and condition, and look for leaks, air locks or contamination
5. Inspect the valve's wiring and connector for damage, corrosion, water ingress and poor pin tension
6. Using a suitable scan tool, command the valve through its actuator test and compare commanded and actual position, and listen and feel for movement
7. Check the coolant pump operation and verify coolant flow and temperature difference across the battery circuit
8. Test the valve supply, ground and signal circuits against the manufacturer's data, and check for applicable software updates for the model

How to fix

• Replace the coolant control valve or its actuator if it is seized or fails the actuator test
• Repair or replace damaged wiring, terminals or connectors to the valve
• Top up or refill with the specified coolant and bleed the battery cooling circuit using the manufacturer's procedure
• Clear blockages or replace restricted hoses, the chiller or heat exchanger as found
• Replace a faulty pump or temperature sensor if testing shows it is the cause
• Apply a manufacturer software update to the control unit if an outdated calibration is a known cause for the vehicle

Can I keep driving?

Nearby codes

• P0CDFGenericHybrid/EV Battery Pack Coolant Control Valve A Control Circuit/Open
• P0CE1GenericHybrid/EV Battery Pack Coolant Control Valve A Stuck On