U04A0Invalid Data Received From Engine Coolant Pump Control Module
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Engines with an electric main coolant pump carry a pump whose built-in electronics set the speed on request and send back status and fault information. Rheinmetall, for example, builds such pumps for main engine cooling with a LIN interface and extensive self-diagnosis, and Hella notes that electric pumps can stay off after a cold start so the engine warms faster. U04A0 means the engine controller still receives pump messages but finds speed, status or check values implausible. No manufacturer documents this code publicly. It matters for emissions because CARB 1968.2 expects coolant temperature to reach its closed-loop threshold in time, which depends on a correctly controlled pump. U019F and U0672 stand for lost contact. Watch the temperature gauge: the engine may run hot, limit power or keep the fan on.
- What you may notice
- Check engine or coolant temperature warning
- Engine runs hot or the cooling fan runs continuously
- Reduced engine power to protect the engine
- Likely causes
- LikelyPump electronics faulty, often after overheating or coolant ingress
- PossibleLIN or CAN wire or connector at the pump corroded or loose
- PossiblePump running dry or blocked (air in system, debris), reported as error state
- RarePump or engine controller software not matched after replacement
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.