OBD fault code library

Look up any P or U code to see what it means, what causes it, the parts involved and how it gets fixed.

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Fault codes

U0011 Medium Speed CAN Communication Bus Performance

Communication Network System High severity

U0014 Medium Speed CAN Communication Bus (+) High

Communication Network System High severity

U0016 Medium Speed CAN Communication Bus (-) Low

Communication Network System High severity

U0017 Medium Speed CAN Communication Bus (-) High

Communication Network System High severity

U0018 Medium Speed CAN Communication Bus (-) shorted to Bus (+)

Communication Network System High severity

U0022 Low Speed CAN Communication Bus (+) Low

Communication Network System High severity

U0026 Low Speed CAN Communication Bus (-) High

Communication Network System High severity

U0030 Vehicle Communication Bus A (+) Open

Communication Network System High severity

U0034 Vehicle Communication Bus A (-) Low

Communication Network System High severity

U0038 Vehicle Communication Bus B Performance

Communication Network System High severity

U0042 Vehicle Communication Bus B (-) Open

Communication Network System High severity

U0046 Vehicle Communication Bus C

Communication Network System High severity

U0051 Vehicle Communication Bus C (-) Open

Communication Network System High severity

U0054 Vehicle Communication Bus C (-) shorted to Bus C (+)

Communication Network System High severity

U0059 Vehicle Communication Bus D (+) High

Communication Network System High severity