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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P2001 NOx trap efficiency lower than limits
Mercedes Benz Auxiliary Emissions Control High severity
U078A /codes/dtcs/u078a
Communication Network System
U078B /codes/dtcs/u078b
Communication Network System
U078C /codes/dtcs/u078c
Communication Network System
U078E /codes/dtcs/u078e
Communication Network System
U078F /codes/dtcs/u078f
Communication Network System
U0790 /codes/dtcs/u0790
Communication Network System
U0791 /codes/dtcs/u0791
Communication Network System
U0792 /codes/dtcs/u0792
Communication Network System
U0793 /codes/dtcs/u0793
Communication Network System
U0794 /codes/dtcs/u0794
Communication Network System
U0796 /codes/dtcs/u0796
Communication Network System
U0797 /codes/dtcs/u0797
Communication Network System
U0798 /codes/dtcs/u0798
Communication Network System
U0799 /codes/dtcs/u0799
Communication Network System

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