OBD-II / EOBD / DTC

OBD-II code lookup

Understand the code. Check the vehicle. Find the next step.

P0420P0300P0171P0455
PPowertrain
0Code series
420Condition identifier

Browse by system

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PPowertrainP0xxx — P3xxxBBodyB0xxx — B3xxxCChassisC0xxx — C3xxxUNetwork communicationU0xxx — U3xxx

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P0128Coolant temperature below thermostat regulating temperature248 Manufacturer communicationsP0171Fuel system too lean · Bank 1327 Manufacturer communicationsP0300Random or multiple-cylinder misfire1,020 Manufacturer communicationsP0420Catalyst efficiency below threshold · Bank 1350 Manufacturer communicationsP0455Evaporative emission system leak detected · Large leak185 Manufacturer communicationsU0100Lost communication with ECM/PCM A128 Manufacturer communications

Makes

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Ford↗Toyota↗Chevrolet↗Honda↗Mercedes-Benz↗Volkswagen↗Hyundai↗Nissan↗Kia↗Subaru↗Audi↗Jeep↗

Learning center

A code identifies a detected condition, not a part that must automatically be replaced.

Scan worksheet →

01Read a code before replacing a part↗02Save freeze-frame data before clearing↗03Pending, confirmed and permanent codes↗04Does an older bulletin still apply?↗05Read fuel trims in context↗06Readiness is not the same as no fault↗

Codes

6,142

Manufacturer communications

21,215

Makes

106

A code index built from manufacturer communications filed with NHTSA in the United States. Vehicle-specific and enhanced codes are included; this is not a list of universal definitions. Data coverage →