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

P2529 Vacuum Reservoir Press Sensor Circuit Interim
Vehicle Speed and Idle Control System High severity
P2530 Ignition Switch Run Position Circuit
Ignition System High severity
P257D Engine Hood Switch Circuit Range/Performance
Computer Output Circuit High severity
P1693 Short circuit in MIL light
Audi Computer Output Circuit High severity
P1694 Open circuit in MIL light
Audi Computer Output Circuit High severity
P2533 Ignition Switch Run/Start Position Circuit
Ignition System High severity
P2535 Ignition Switch Run/Start Position Circuit High
Ignition System High severity
P2536 Ignition Switch Accessory Position Circuit
Ignition System High severity
P2538 Ignition Switch Accessory Position Circuit High
Ignition System High severity
P2540 Low Press Fuel Sys Sensor Circuit Range/Performance
Fuel and Air Metering High severity
P2542 Low Press Fuel Sys Sensor Circuit High
Fuel and Air Metering High severity
P2543 Low Press Fuel Sys Sensor Circuit Interim
Fuel and Air Metering High severity
P2544 Torque Management Request Input Signal A
Transmission System High severity
P2546 Torque Management Request Input Signal A Low
Transmission System High severity
P2547 Torque Management Request Input Signal A High
Transmission System High severity

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