Hybrid/EV Battery Pack Coolant Control Valve C Control Circuit/Open
What it means
The hybrid/EV battery pack coolant control valve C control circuit is open, meaning the module sees a broken or disconnected path. The valve directs coolant through the high-voltage battery loop to heat or cool the pack as needed.
Can I keep driving? Usually yes for a short, gentle trip, but heat can damage the battery or drive parts; if power drops or a warning shows, stop and get it checked. Do not open high-voltage (orange) cables or covers yourself; leave that to a trained technician.
What this part does
This valve directs the flow of coolant through the high-voltage battery's cooling circuit, deciding whether coolant goes through the battery, a chiller or a bypass path. The thermal management system adjusts it to keep the battery at a suitable temperature. The battery is part of a high-voltage system, so servicing it is for trained people. A fault may bring a warning, reduced power or slower charging.
Common symptoms
What you'll notice
- Warning lamp illuminated on the dashboard
- Reduced power or performance of the vehicle
- Inefficient or decreased fuel economy
- Difficulty starting the engine or engine stalling
- Overheating of the hybrid/EV battery pack
Common causes
Most likely first
- Malfunction or failure of the hybrid/EV battery pack coolant control valve
- Faulty wiring or connections in the C control circuit
- Open circuit in the C control circuit
- Issues with the hybrid/EV battery pack coolant control module
- Malfunctioning sensor or sensor circuit related to the coolant control valve
How to diagnose & fix
Work through it in order
- Check and repair any wiring or connectors related to the hybrid/EV battery pack coolant control valve C control circuit.
- Inspect the hybrid/EV battery pack coolant control valve C for any signs of damage or malfunction, and replace if necessary.
- Inspect the hybrid/EV battery pack coolant system for any leaks or blockages, and address any issues found.
Related codes
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