U0672 code meaning
Lost Communication With Engine Coolant Pump
Network system Generic code U06xx codes Check engine light
What U0672 means
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.
U0672 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0672
- Check engine light immediately
- Rising coolant temperature or overheating warning
- Weak cabin heating
- Reduced engine power to protect the engine
Common causes of U0672
- Most 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
- Less likelyPump relay or fuse supplying the pump faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Engine coolant pumpVehicle bus wiring
What each part of U0672 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 72 | The exact fault in that area. |
What to do next
- Note U0672 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0672
What does U0672 mean?
U0672 means "Lost Communication With Engine Coolant Pump". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with U0672?
Drive gently and only to a workshop. With U0672 the car can go into limp mode (reduced power) to protect itself.
Will U0672 fail an emissions test?
Yes, it can. U0672 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0672 to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will U0672 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.