Coolant Pump A Control Circuit / Open
The controller cannot drive the electric coolant pump A control line. Without circulation, engine and aftertreatment can overheat or warm up incorrectly.
Affected components
- Coolant pump a
- Pump relay
- Wiring harness
Common causes
- High likelihood: Open pump motor winding
- Medium likelihood: Broken control wire to the pump
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.