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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U0539 /codes/dtcs/u0539
Communication Network System
U053A /codes/dtcs/u053a
Communication Network System
U053C /codes/dtcs/u053c
Communication Network System
U053E /codes/dtcs/u053e
Communication Network System
U053F /codes/dtcs/u053f
Communication Network System
U0540 /codes/dtcs/u0540
Communication Network System
U0542 /codes/dtcs/u0542
Communication Network System
U0543 /codes/dtcs/u0543
Communication Network System
U0544 /codes/dtcs/u0544
Communication Network System
U0545 /codes/dtcs/u0545
Communication Network System
U0546 /codes/dtcs/u0546
Communication Network System
U0548 /codes/dtcs/u0548
Communication Network System
U0549 /codes/dtcs/u0549
Communication Network System
U054A /codes/dtcs/u054a
Communication Network System
U054B /codes/dtcs/u054b
Communication Network System

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