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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U0638 /codes/dtcs/u0638
Communication Network System
U0639 /codes/dtcs/u0639
Communication Network System
U063B /codes/dtcs/u063b
Communication Network System
U063C /codes/dtcs/u063c
Communication Network System
U063D /codes/dtcs/u063d
Communication Network System
U063E /codes/dtcs/u063e
Communication Network System
U063F /codes/dtcs/u063f
Communication Network System
U0640 /codes/dtcs/u0640
Communication Network System
U0641 /codes/dtcs/u0641
Communication Network System
U0643 /codes/dtcs/u0643
Communication Network System
U0645 /codes/dtcs/u0645
Communication Network System
U0646 /codes/dtcs/u0646
Communication Network System
U0647 /codes/dtcs/u0647
Communication Network System
U0648 /codes/dtcs/u0648
Communication Network System
U0649 /codes/dtcs/u0649
Communication Network System

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