DTC codes
Look up an OBD-II fault code: what it means on every car or on your make, and how to track it down.
How to read a code
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 4
- AreaAuxiliary emission controls
- 20
- FaultThe specific fault in that area
Read the code
Note every stored and pending code your scanner shows, such as P0420.
Find it
Search by code or by words. For a manufacturer code (P1, B1, C1, U1) pick your make: its meaning differs by make.
Open the code
Its page explains the symptoms, likely causes, the checks to run and the fixes.
- P1150Mercury · PowertrainLack of Upstream Heated Oxygen Sensor Switch Adaptive Fuel Limit Bank 2
- P1150Other · PowertrainLack Of HO2S21 Switch - Adaptive Fuel At Limit
- P1150Subaru · PowertrainFront Oxygen Sensor Heater Circuit High Input
- P1150Toyota · PowertrainAir/Fuel Sensor Circuit Range Performance Bank 1 Sensor 2
- P1150Volkswagen · PowertrainOxygen Sensor Control Bank 2 Out Of Range
- P1151Generic · PowertrainLack Of HO2S21 Switch - Sensor Indicates Lean
- P1151BMW · PowertrainO2 Sensor Heater Circuit Signal Intermittent Bank 2 Sensor 1
- P1151Ford · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2
- P1151Lincoln · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2
- P1151Mazda · PowertrainHO2S Bank 2 Sensor 1 Signal Below 0.45v AF Ratio Too Lean
- P1151Mercury · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2
- P1151Other · PowertrainLack Of HO2S21 Switch - Sensor Indicates Lean
- P1151Subaru · PowertrainRear Oxygen Sensor Heater Circuit High Input
- P1151Volkswagen · PowertrainBank 1 Long Term Fuel Trim Range 1 Lower Lean Limit Exceeded
- P1152BMW · PowertrainO2 Sensor Heater Circuit Low Voltage Bank 2 Sensor 1
- P1152Ford · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 2
- P1152Lincoln · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 2
- P1152Mazda · PowertrainHO2S Bank 2 Sensor 1 Signal Above 0.45v AF Ratio Too Rich
- P1152Mercury · PowertrainLack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 2
- P1152Other · PowertrainLack Of HO2S21 Switch - Sensor Indicates Rich
- P1152Volkswagen · PowertrainBank 1 Long Term Fuel Trim Range 2 Lower Lean Limit Exceeded
- P1153Generic · PowertrainBank 2 Fuel Control Shifted Lean
- P1153BMW · PowertrainO2 Sensor Heater Circuit High Voltage Bank 2 Sensor 1
- P1153Buick · PowertrainHO2S Insufficient Switching
- P1153Cadillac · PowertrainHO2S Insufficient Switching
- P1153Chevrolet · PowertrainHO2S Insufficient Switching
- P1153Chrysler · PowertrainHO2S Insufficient Switching
- P1153Ford · PowertrainBank 2 Fuel Control Shifted Lean
- P1153GM · PowertrainHO2S Insufficient Switching
- P1153GMC · PowertrainHO2S Insufficient Switching
