U0647: The engine electronics coolant pump B is not answering on the car network
The engine electronics coolant pump B is not answering on the car network. It is usually that control unit, its power supply or the network wiring.
| Code | U0647 |
|---|---|
| System | Communication network |
| Group | U06xx, Lost communication with sensors and control units |
| Type | Generic: it means the same on every make |
How to read and clear U0647 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see U0647 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- U0643 The turbocharger A temperature sensor is not answering on the car network
- U0644 The wastegate position sensor A is not answering on the car network
- U0645 The active air deflector module is not answering on the car network
- U0646 The engine electronics coolant pump A is not answering on the car network
- U0648 The engine electronics coolant pump C is not answering on the car network
- U0649 The coolant pump D is not answering on the car network
- U064A The high voltage battery current sensor A is not answering on the car network
- U064B The high voltage battery current sensor B is not answering on the car network
What does code U0647 mean?
The engine electronics coolant pump B is not answering on the car network. It is usually that control unit, its power supply or the network wiring.
How do you clear U0647?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, U0647 comes back.
