U1900High severity

CAN Communication Bus Fault

A general fault on the CAN communication bus.

Safe to Drive?
Yes

Informational only. Consult a qualified mechanic.

Estimated Repair Cost
$100 - $1,000
Common Causes
  • CAN bus wiring damage
  • Faulty module
  • Aftermarket device interference
Recommended Action

Check for aftermarket devices on OBD port. Diagnose CAN bus.

What does U1900 mean?

The U1900 OBD-II diagnostic trouble code (DTC) indicates: can communication bus fault. This is a high-severity network code that your vehicle's onboard diagnostics system triggers when a general fault on the can communication 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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