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

U0024 Low Speed CAN Communication Bus (-) Open

Communication Network System High severity

U0025 Low Speed CAN Communication Bus (-) Low

Communication Network System High severity

U0027 Low Speed CAN Communication Bus (-) shorted to Bus (+)

Communication Network System High severity

U0028 Vehicle Communication Bus A

Communication Network System High severity

U0029 Vehicle Communication Bus A Performance

Communication Network System High severity

U0031 Vehicle Communication Bus A (+) Low

Communication Network System High severity

U0032 Vehicle Communication Bus A (+) High

Communication Network System High severity

U0033 Vehicle Communication Bus A (-) Open

Communication Network System High severity

U0035 Vehicle Communication Bus A (-) High

Communication Network System High severity

U0036 Vehicle Communication Bus A (-) shorted to Bus A (+)

Communication Network System High severity

U0037 Vehicle Communication Bus B

Communication Network System High severity

U0039 Vehicle Communication Bus B (+) Open

Communication Network System High severity

U0040 Vehicle Communication Bus B (+) Low

Communication Network System High severity

U0041 Vehicle Communication Bus B (+) High

Communication Network System High severity

U0043 Vehicle Communication Bus B (-) Low

Communication Network System High severity