Coolant Pump B Control Circuit Performance/Stuck Off
The second electric coolant pump is commanded on but does not run. Cooling demand of the connected loop is not satisfied.
Affected components
- Coolant pump b
- Pump motor
Common causes
- High likelihood: Pump motor seized by sediment
- Medium likelihood: Cracked rotor magnet decouples drive
- Low likelihood: Carbon or debris buildup preventing free movement
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.