OBD-II Fault Codes
Look up a code from your scanner. Every code page shows the risk first, then what it means, possible causes and how it is diagnosed.
Codes and titles follow SAE J2012 · Maker notes verified per make and engine · How we verify
Browse by system
Powertrain codes by subsystem
P00xxFuel, air metering and auxiliary emission controlsP01xxFuel and air meteringP02xxFuel and air metering (injector circuit)P03xxIgnition system and misfireP04xxAuxiliary emission controlsP05xxVehicle speed, idle control and auxiliary inputsP06xxComputer and auxiliary outputsP07xxTransmissionP2xxxAdditional generic codes (fuel, air, emissions)
Most searched codes
P0420Catalyst System Efficiency Below Threshold (Bank 1)Normal riskP0300Random/Multiple Cylinder Misfire DetectedHigh riskP0171System Too Lean (Bank 1)Normal riskP0128Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)Normal riskP0455Evaporative Emission System Leak Detected (Large Leak)Normal riskP0401Exhaust Gas Recirculation "A" Flow Insufficient DetectedNormal riskP0442Evaporative Emission System Leak Detected (Small Leak)Normal riskP0700Transmission Control System (MIL Request)Normal riskP0299Turbocharger/Supercharger "A" Underboost ConditionNormal riskP0172System Too Rich (Bank 1)Normal riskP0135O2 Sensor Heater Circuit (Bank 1 Sensor 1)Normal riskP0113Intake Air Temperature Sensor 1 Circuit HighNormal risk
How to read a fault code
The letter is the system, the first digit says generic or maker-specific, the next digit the subsystem and the last two the exact fault. Fault Code Lookup →All fault codes
B0001Driver Frontal Stage 1 Deployment ControlHigh riskB0002Driver Frontal Stage 2 Deployment ControlHigh riskB0003Driver Frontal Stage 3 Deployment ControlHigh riskB0004Driver Knee Bolster Deployment ControlHigh riskB0010Passenger Frontal Stage 1 Deployment ControlHigh riskB0011Passenger Frontal Stage 2 Deployment ControlHigh riskB0012Passenger Frontal Stage 3 Deployment ControlHigh riskB0013Passenger Knee Bolster Deployment ControlHigh riskB0020Left Side Airbag Deployment ControlHigh riskB0021Left Curtain Airbag Deployment Control 1High riskB0022Left Curtain Airbag Deployment Control 2High riskB0028Right Side Airbag Deployment ControlHigh riskB0029Right Curtain Airbag Deployment Control 1High riskB002ARight Curtain Airbag Deployment Control 2High riskB0030Second Row Left Side Airbag Deployment ControlHigh riskB0038Second Row Right Side Airbag Deployment ControlHigh riskB0050Driver Seat Belt SensorHigh riskB0052Passenger Seat Belt SensorHigh riskB0070Driver Seat Belt Pretensioner "A" Deployment ControlHigh riskB0072Passenger Seat Belt Pretensioner "A" Deployment ControlHigh riskB0080Driver Seat Belt Load Limiter Deployment ControlHigh riskB0082Passenger Seat Belt Load Limiter Deployment ControlHigh riskB0090Left Frontal Restraints SensorHigh riskB0091Left Side Restraints Sensor 1High riskB0095Right Frontal Restraints SensorHigh riskB0096Right Side Restraints Sensor 1High riskB0099Rollover SensorHigh riskB00A0Occupant Classification SystemHigh riskB00C0Passenger Occupant Classification Sensor "A"High riskB00DFPassenger Restraints Disable SwitchHigh risk