Error code

OBD2 U0003

OBD2U0003
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

High Speed CAN Communication Bus (Open).

Severity

severeDriving may be possible but is not recommended due to potential safety risks.

Summary

U0003 indicates an open circuit in the high-speed Controller Area Network (CAN) data bus, which is a critical communication network for vehicle systems.

Common Causes

  • Open circuit in the high-speed CAN data bus cable or connector
  • Faulty module connected to the high-speed CAN

Fixes

FAQ

What does U0003 mean?

U0003 indicates an issue with the high-speed CAN data bus, specifically an open circuit.

How serious is this code?

This code is severe because it affects critical communication between vehicle systems and can lead to safety issues if not addressed.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.