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

U0044 Vehicle Communication Bus B (-) High

Communication Network System High severity

U0045 Vehicle Communication Bus B (-) shorted to Bus B (+)

Communication Network System High severity

U0047 Vehicle Communication Bus C Performance

Communication Network System High severity

U0048 Vehicle Communication Bus C (+) Open

Communication Network System High severity

U0050 Vehicle Communication Bus C (+) High

Communication Network System High severity

U0052 Vehicle Communication Bus C (-) Low

Communication Network System High severity

U0053 Vehicle Communication Bus C (-) High

Communication Network System High severity

U0055 Vehicle Communication Bus D

Communication Network System High severity

U0056 Vehicle Communication Bus D Performance

Communication Network System High severity

U0057 Vehicle Communication Bus D (+) Open

Communication Network System High severity

U0058 Vehicle Communication Bus D (+) Low

Communication Network System High severity

U0060 Vehicle Communication Bus D (-) Open

Communication Network System High severity

U0061 Vehicle Communication Bus D (-) Low

Communication Network System High severity

U0062 Vehicle Communication Bus D (-) High

Communication Network System High severity

U0064 Vehicle Communication Bus E

Communication Network System High severity