Engine Coolant Pump Overspeed/Air In System
The coolant pump speed feedback is higher than the commanded value with no resistance from coolant. Indicates air in the cooling loop or low coolant level so the pump spins free.
Affected components
- Engine coolant pump
- Cooling system
- Coolant reservoir
Common causes
- High likelihood: Low coolant level due to leak or improper fill
- Medium likelihood: Air pocket trapped in the cooling loop
Diagnostic notes
- The malfunction indicator lamp may illuminate
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.