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

P1673 Invalid speed signals from ABS system

Audi Computer Output Circuit High severity

P2151 Fuel Injector Group B Supply Voltage Circuit High

Injector Circuit High severity

P2153 Fuel Injector Group C Supply Voltage Circuit Low

Injector Circuit High severity

P2154 Fuel Injector Group C Supply Voltage Circuit High

Injector Circuit High severity

P2156 Fuel Injector Group D Supply Voltage Circuit Low

Injector Circuit High severity

P2157 Fuel Injector Group D Supply Voltage Circuit High

Injector Circuit High severity

P2171 Exhaust Press Regulator Vent Solenoid Ctrl Circuit High

Auxiliary Emissions Control Medium severity

P2172 Throttle Actuator Ctrl Sys-Sudden High Airflow Detected

Fuel and Air Metering High severity

P2174 Throttle Actuator Ctrl Sys-Sudden Low Airflow Detected

Fuel and Air Metering High severity

P2175 Throttle Actuator Ctrl Sys-Low Airflow Detected

Fuel and Air Metering High severity

P2201 NOx Sensor Circuit Range/Performance Bank1

Auxiliary Emissions Control High severity

P2202 NOx Sensor Circuit Low Input Bank1

Auxiliary Emissions Control High severity

P2203 NOx Sensor Circuit High Input Bank1

Auxiliary Emissions Control High severity

P2205 NOx Sensor Heater Ctrl Circuit/Open Bank1

Auxiliary Emissions Control High severity

P2206 NOx Sensor Heater Ctrl Circuit Low Bank1

Auxiliary Emissions Control High severity