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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U21A2 /codes/dtcs/u21a2
Communication Network System
U21A3 /codes/dtcs/u21a3
Communication Network System
U21A4 /codes/dtcs/u21a4
Communication Network System
U21A5 /codes/dtcs/u21a5
Communication Network System
U21A6 /codes/dtcs/u21a6
Communication Network System
U21A7 /codes/dtcs/u21a7
Communication Network System
U21A8 /codes/dtcs/u21a8
Communication Network System
U21A9 /codes/dtcs/u21a9
Communication Network System
U21AA /codes/dtcs/u21aa
Communication Network System
U21AB /codes/dtcs/u21ab
Communication Network System
U21AC /codes/dtcs/u21ac
Communication Network System
U21AD /codes/dtcs/u21ad
Communication Network System
U21AE /codes/dtcs/u21ae
Communication Network System
U21AF /codes/dtcs/u21af
Communication Network System
U21B0 /codes/dtcs/u21b0
Communication Network System

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