Engine Coolant Bypass Valve B Control Circuit Low
Voltage on the second coolant bypass valve control line is below the expected window. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Affected components
- Coolant bypass valve b
- Solenoid
- Wiring harness
Common causes
- High likelihood: Control wire shorted to ground
- Medium likelihood: Internal short in solenoid coil
- Low likelihood: Connector pins corroded - high contact resistance
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.