What it means
During cold start, the engine coolant pump runs below the calibrated minimum speed. Cold viscosity load too high or pump weak.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The engine coolant pump circulates coolant, and during a cold start the control module monitors its speed. This code sets when pump speed falls below the calibrated minimum, which can indicate excessive load from cold coolant or degraded pump output.
Common causes
Most likely first.
- Cold coolant viscosity too high
- Pump output degraded
Symptoms
- Check-engine light
- Engine may take longer to warm up
- Weak cabin heat in cold weather
- Possible engine temperature warning if cooling is inadequate
How to diagnose it
- Read freeze-frame data and scan-tool pump-speed and coolant-temperature values to confirm the fault occurred during a cold start.
- Check coolant level and condition, and look for leaks or signs that the coolant is contaminated or unsuitable for the vehicle.
- Inspect the pump connector, wiring, and accessible drive components for damage, poor connections, or obstruction.
- Compare commanded and reported pump speed during a cold-start test, if available, and note whether the pump responds consistently.
- Test pump operation and its electrical supply using the manufacturer's procedure to distinguish a weak pump from a circuit or load issue.
Common fixes
- Correct the coolant level or condition using the specified coolant and service procedure.
- Repair damaged or poorly connected wiring or connectors at the coolant pump.
- Remove an identified obstruction affecting pump operation.
- Replace the coolant pump if testing confirms its output is degraded.
Can I keep driving?
Avoid long trips or heavy loads until the cooling system is checked, especially in cold conditions. If a temperature warning appears or the engine begins overheating, stop safely; reduced pump speed can impair cooling and risk engine damage.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.