Powertrain Emissions Diagnostic Trouble Codes

Complete list of Powertrain emissions DTC codes with free diagnostic guides.

Below you'll find every known DTC code for the Powertrain Emissions subsystem with step-by-step diagnostic and repair instructions. 19 guides are available — covering causes, symptoms, and repair costs. Use the table to find your specific code, or browse our full Powertrain DTC code library for other subsystems.

DTC Code Meaning Severity Time
P0400 The engine control module detects that the EGR system is not moving the correct ... medium 30‑60 minutes P0401 The engine control module (ECM) has detected that the Exhaust Gas Recirculation ... medium 30‑60 minutes P0402 The engine control module (ECM) has detected that more exhaust gas is being reci... medium 30-60 minutes P0410 The engine control module has detected that the secondary‑air injection (SAI) sy... medium 30‑60 minutes P0411 The engine control module (ECM) has detected that the secondary‑air injection (S... medium 30-60 minutes P0420 The P0420 code means your catalytic converter is not cleaning exhaust gases as e... medium 30-60 minutes P0430 The engine control module has determined that the catalytic converter on bank 2 ... medium 30‑60 minutes P0441 The engine control module has detected that the EVAP purge valve is allowing too... low 30-60 minutes P0442 The engine control module has found a small leak in the evaporative emissions (E... low 30-60 minutes P0443 The engine control module has detected a problem with the electrical circuit tha... medium 30-60 minutes P0446 The engine control module has detected a problem with the vent control circuit o... low 30‑60 minutes P0449 The engine control module has detected a problem with the vent valve or its cont... medium 30‑60 minutes P0451 The engine control module has detected that the EVAP‑system pressure sensor is r... medium 30-60 minutes P0452 The engine control module has detected that the pressure sensor in the evaporati... medium 30-60 minutes P0455 The engine control module has sensed a large leak in the evaporative emissions (... medium 30-60 minutes P0456 The engine control module has sensed a tiny leak in the evaporative emissions (E... low 30‑60 minutes P0496 The PCM has detected that the EVAP purge valve is allowing more vapor flow than ... medium 30-60 minutes P1457 The engine control module has sensed that the evaporative emissions (EVAP) contr... low 30‑60 minutes SYMPTOM-FAILED-EMISSIONS The powertrain control module has determined that the vehicle did not meet the r... medium 30-60 minutes

About Powertrain Emissions Trouble Codes

Powertrain emissions diagnostic trouble codes are triggered when the vehicle's onboard computer detects a malfunction in the emissions subsystem. These codes help you quickly identify the problem without visiting a dealership. Our guides walk you through each DTC code with step-by-step diagnostic procedures, tools needed, and when to call a professional mechanic.

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