U1000High severity

Class 2 Communication Malfunction

A general communication malfunction on the Class 2 serial data bus.

Safe to Drive?
Yes

Informational only. Consult a qualified mechanic.

Estimated Repair Cost
$100 - $800
Common Causes
  • Wiring short/open on data bus
  • Faulty module
  • Connector corrosion
Recommended Action

Diagnose the data bus for shorts or opens. Identify the offending module.

What does U1000 mean?

The U1000 OBD-II diagnostic trouble code (DTC) indicates: class 2 communication malfunction. This is a high-severity network code that your vehicle's onboard diagnostics system triggers when a general communication malfunction on the class 2 serial data bus. If your check engine light is on with this code, the vehicle is generally safe to drive, but you should have it inspected soon.

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