U0672Lost Communication With Engine Coolant Pump
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- GM's 2.0 L LSY and 2.7 L L3B four-cylinders circulate coolant with an electric main pump that the engine controller commands over LIN. U0672 sets when the pump's response frame MWP_Rsp is missing for at least 250 ms (25OBDG03B; same logic in 19OBDG03D for the L3B) once the LIN channel is up, the relay is powered and battery voltage exceeds 11 V; as a Type A fault it turns the MIL on at once. GM bulletin PIP5863C covers 2019-2024 Silverado/Sierra 1500, Colorado/Canyon, Blazer, Acadia, Envision and Cadillac CT4 to XT6: check terminals and crimps, unplug and reconnect the pump, clear the code; if it stays away, release the car. U019F names a separate pump control module, U04A0 its invalid data. Watch engine temperature.
- What you may notice
- Check engine light immediately
- Rising coolant temperature or overheating warning
- Weak cabin heating
- Reduced engine power to protect the engine
- Likely causes
- LikelyPoor terminal tension, crimp or lock at the electric pump connector
- PossibleLIN, supply or ground wire to the pump chafed or contaminated
- PossiblePump electronics or motor failed
- RarePump relay or fuse supplying the pump faulty
- 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: €40 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.