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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U21C4 /codes/dtcs/u21c4
Communication Network System
U21C5 /codes/dtcs/u21c5
Communication Network System
U21C8 /codes/dtcs/u21c8
Communication Network System
U21C9 /codes/dtcs/u21c9
Communication Network System
U21CA /codes/dtcs/u21ca
Communication Network System
U21CC /codes/dtcs/u21cc
Communication Network System
U21CD /codes/dtcs/u21cd
Communication Network System
U21CE /codes/dtcs/u21ce
Communication Network System
U21CF /codes/dtcs/u21cf
Communication Network System
U21D0 /codes/dtcs/u21d0
Communication Network System
U21D1 /codes/dtcs/u21d1
Communication Network System
U21D2 /codes/dtcs/u21d2
Communication Network System
U21D3 /codes/dtcs/u21d3
Communication Network System
U21D5 /codes/dtcs/u21d5
Communication Network System
U21D6 /codes/dtcs/u21d6
Communication Network System

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