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

P0155 O2 Sensor Heater Circuit Malfunction Bank 2 Sensor 1

Generic Fuel and Air Metering Medium severity

P0156 O2 Sensor Circuit Malfunction Bank 2 Sensor 2

Generic Fuel and Air Metering Medium severity

P0157 O2 Sensor Circuit Low Voltage Bank 2 Sensor 2

Generic Fuel and Air Metering Medium severity

P0159 O2 Sensor Circuit Slow Response Bank 2 Sensor 2

Generic Fuel and Air Metering Medium severity

P0160 O2 Sensor Circuit No Activity Detected Bank 2 Sensor 2

Generic Fuel and Air Metering Medium severity

P0162 O2 Sensor Circuit Malfunction Bank 2 Sensor 3

Generic Fuel and Air Metering Medium severity

P0163 O2 Sensor Circuit Low Voltage Bank 2 Sensor 3

Generic Fuel and Air Metering Medium severity

P0165 O2 Sensor Circuit Slow Response Bank 2 Sensor 3

Generic Fuel and Air Metering Medium severity

P0166 O2 Sensor Circuit No Activity Detected Bank 2 Sensor 3

Generic Fuel and Air Metering Medium severity

P0167 O2 Sensor Heater Circuit Malfunction Bank 2 Sensor 3

Generic Fuel and Air Metering Medium severity

P0169 Incorrect Fuel Composition

Generic Fuel and Air Metering High severity

P0170 Fuel Trim Malfunction Bank 1

Generic Fuel and Air Metering High severity

P0171 System Too Lean Bank 1

Generic Fuel and Air Metering High severity

P0173 Fuel Trim Malfunction Bank 2

Generic Fuel and Air Metering High severity

P0174 System Too Lean Bank 2

Generic Fuel and Air Metering High severity