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

P1974 Issue in secondary air injection valve (controls emission)

Volkswagen Auxiliary Emissions Control High severity

P1977 Issue in secondary air injection valve (controls emission)

Volkswagen Auxiliary Emissions Control High severity

P1980 Issue in secondary air injection valve (controls emission)

Volkswagen Auxiliary Emissions Control High severity

P1983 Issue in exhaust gas temperature sensor

Volkswagen Auxiliary Emissions Control High severity

P1987 Issue in brake temperature sensor

Volkswagen Vehicle Speed and Idle Control System High severity

P1990 Issue in exhaust cooling system

Volkswagen Auxiliary Emissions Control High severity

P1991 Internal malfunction detected in ECM

Volkswagen Computer Output Circuit High severity

P1996 Friction in camshaft higher than limits

Volkswagen Ignition System High severity

P1999 Friction in camshaft higher than limits

Volkswagen Ignition System High severity

P1603 Internal malfunction detected in ECM

Audi Computer Output Circuit High severity

P1606 Invalid torque signals from ABS

Audi Computer Output Circuit High severity

P1609 Crash shut down activated (ECM)

Audi Computer Output Circuit High severity

P1612 Coding error in Electronic control module

Audi Computer Output Circuit High severity

P1617 Issue in glow plug

Audi Ignition System High severity

P1620 Issue in Engine Coolant Temperature sensor

Audi Fuel and Air Metering High severity