U0636
Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A
U0636 is an OBD-II diagnostic trouble code meaning: Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A. Common causes: open or short circuit in valve control circuit, cooling solenoid valve malfunction. Estimated repair cost: $28–167.
Symptoms
- Hybrid system warning light comes on
- Hybrid system power reduction
- High voltage battery overheating
- Speed limit
- Unstable operation of the cooling system
Causes
- Open or short circuit in valve control circuit
- Cooling solenoid valve malfunction
- Damage to wiring harness or connectors
- Problems with the car's CAN bus
- Control unit software error
How to Fix
- Check the integrity of the valve circuit wiring and connectors
- Test solenoid valve resistance
- Scan the CAN bus for communication errors
- Replace faulty cooling valve if necessary
- Update control unit software
Related codes
Error U0636 by Vehicle Brand
FAQ
What does the U0636 code mean?
U0636 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A
What causes a U0636 error code?
The most common causes of U0636 include: Open or short circuit in valve control circuit; Cooling solenoid valve malfunction; Damage to wiring harness or connectors; Problems with the car's CAN bus.
How do I fix a U0636 diagnostic trouble code?
To fix U0636: Check the integrity of the valve circuit wiring and connectors. Test solenoid valve resistance. Scan the CAN bus for communication errors. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U0636?
Limited driving only, diagnose soon
How much does it cost to fix U0636?
The estimated repair cost for U0636 is $28–167. Actual cost depends on your vehicle, location, and labor rates.
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