U063C

Lost Communication With Coolant Bypass Valve Actuator B

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$17–67 (est.)

Symptoms

Check Engine Light Is On
Unstable engine operation
Increased engine temperature
Reduced cooling system efficiency
Errors in climate control operation

Causes

Open or short circuit in valve circuit
Coolant bypass valve malfunction
Connector problems or contact corrosion
Engine ECU malfunction
Wiring Harness Problems

How to Fix

Check valve control circuit integrity
Inspect connectors and contacts for damage
Check valve resistance and operation
Scan the ECU for additional errors
Replace the coolant bypass valve if necessary.

Related codes

U063B U063D U063E