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
P1399
Wheel Speed Sensor 2 G-Sensor Circuit Intermittent
Audi
Vehicle Speed and Idle Control System
High severity
P1400
EGR Valve Power Stage Circuit Electrical Malfunction
Audi
Auxiliary Emissions Control
Medium severity
P1409
Tank Ventilation Valve Circuit Electrical Malfunction
Audi
Auxiliary Emissions Control
Medium severity
P1413
EGR Differential Pressure Sensor Signal Too High
Audi
Auxiliary Emissions Control
Medium severity
P1422
Secondary Air Injection Valve Circuit Short To B
Audi
Auxiliary Emissions Control
Medium severity
P1430
Brake System Vacuum Pump Activation Open Circuit/Short To Positive
Audi
Vehicle Speed and Idle Control System
Low severity
P1431
Brake System Vacuum Pump Activation Open Circuit/Short To Ground
Audi
Vehicle Speed and Idle Control System
Low severity
P1438
EGR Valve 2 Open Circuit or Short Circuit to Ground
Audi
Auxiliary Emissions Control
Medium severity
P1441
EGR Vacuum Regulator Solenoid Valve Open/Short To Ground
Audi
Auxiliary Emissions Control
Medium severity
P1449
Catalyst Temperature Sensor 2 Circuit Open/Short to B
Audi
Auxiliary Emissions Control
Medium severity
P1459
Exhaust Gas Temperature Sensor 2 Range/Performance
Audi
Vehicle Speed and Idle Control System
Medium severity
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