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
P1178
O2 Sensor Signal Circuit Slow Switching From Rich to Lean Bank 1 Sensor 1
BMW
Fuel and Air Metering
Medium severity
P1180
O2 Sensor Signal Circuit Slow Switching From Rich to Lean Bank 1 Sensor 2
BMW
Fuel and Air Metering
Medium severity
P1199
O2S Heater Circuit Bank 2 Sensor 2 Electrical Malfunction
BMW
Fuel and Air Metering
Medium severity
P1221
Pedal Position Sensor 2 Range/Performance Problem
BMW
Vehicle Speed and Idle Control System
Low severity
P1224
Throttle Position Sensor B Out of Self-Test Range
BMW
Vehicle Speed and Idle Control System
Low severity
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