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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U21D7 /codes/dtcs/u21d7
Communication Network System
U21D9 /codes/dtcs/u21d9
Communication Network System
U21DA /codes/dtcs/u21da
Communication Network System
U21DB /codes/dtcs/u21db
Communication Network System
U21DC /codes/dtcs/u21dc
Communication Network System
U21DE /codes/dtcs/u21de
Communication Network System
U21DF /codes/dtcs/u21df
Communication Network System
U21E0 /codes/dtcs/u21e0
Communication Network System
U21E1 /codes/dtcs/u21e1
Communication Network System
U21E2 /codes/dtcs/u21e2
Communication Network System
U21E3 /codes/dtcs/u21e3
Communication Network System
U21E4 /codes/dtcs/u21e4
Communication Network System
U21E6 /codes/dtcs/u21e6
Communication Network System
U21E7 /codes/dtcs/u21e7
Communication Network System
U21E8 /codes/dtcs/u21e8
Communication Network System

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