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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U121C /codes/dtcs/u121c
Communication Network System
U121D /codes/dtcs/u121d
Communication Network System
U121E /codes/dtcs/u121e
Communication Network System
U121F /codes/dtcs/u121f
Communication Network System
U122B /codes/dtcs/u122b
Communication Network System
U122C /codes/dtcs/u122c
Communication Network System
U122D /codes/dtcs/u122d
Communication Network System
U123A /codes/dtcs/u123a
Communication Network System
U123B /codes/dtcs/u123b
Communication Network System
U123C /codes/dtcs/u123c
Communication Network System
U123D /codes/dtcs/u123d
Communication Network System
U123F /codes/dtcs/u123f
Communication Network System
U124A /codes/dtcs/u124a
Communication Network System
U124B /codes/dtcs/u124b
Communication Network System
U124C /codes/dtcs/u124c
Communication Network System

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