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
P1121
HO2S Sensor Heater Circuit Short To Ground Bank 2 Sensor 2
Volkswagen
Fuel and Air Metering
Medium severity
P1125
Long Term Fuel Trim Adjustment Bank 2 System Too Rich
Volkswagen
Fuel and Air Metering
High severity
P1133
HO2S Heater Circuit- Bank 1 & 2 Sensor 1 Electrical Malfunction
Volkswagen
Fuel and Air Metering
Medium severity
P1136
Long Term Fuel Trim Add Fuel B1 System Too Lean
Volkswagen
Fuel and Air Metering
High severity
P1137
Long Term Fuel Trim Add Fuel B1 System Too Rich
Volkswagen
Fuel and Air Metering
High severity
P1152
Bank 1 Long Term Fuel Trim Range 2 Lean Lower Limit Exceeded
Volkswagen
Fuel and Air Metering
High severity
P1156
Manifold Absolute Pressure Sensor Open/Short To Ground
Volkswagen
Fuel and Air Metering
High severity
P1157
Manifold Absolute Pressure Sensor Supply Voltage
Volkswagen
Fuel and Air Metering
High severity
P1161
Intake Air Temperature Sensor Open/Short To Positive
Volkswagen
Fuel and Air Metering
High severity
P1165
Bank 1 Long Term Fuel Trim Range 1 Rich Upper Limits Exceeded
Volkswagen
Fuel and Air Metering
High severity
P1171
Throttle Actuation Potentiometer Signal 2 Range/Performance
Volkswagen
Fuel and Air Metering
High severity
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