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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Fault codes
U0302
Internal malfunction detected in Transmission control module (TCM)
Mercedes Benz
Communication Network System
High severity
U0303
Internal malfunction detected in Transmission control module (TCM)
Mercedes Benz
Communication Network System
High severity
U0321
Internal malfunction detected in Ride level control module
Mercedes Benz
Communication Network System
High severity
U0326
Internal malfunction detected in Immobilizer control module
Mercedes Benz
Communication Network System
High severity
U0327
Internal malfunction detected in Vehicle security control module
Mercedes Benz
Communication Network System
High severity
P00AF
Issue in turbocharger or supercharger boost pressure control circuit
Audi
Injector Circuit
High severity
P00AF
Issue in turbocharger or supercharger boost pressure control circuit
Volkswagen
Injector Circuit
High severity
P00AF
Issue in turbocharger or supercharger boost pressure control circuit
Skoda
Injector Circuit
High severity
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