Powertrain (P-Codes) are diagnostic trouble codes related to the engine, transmission, fuel/air delivery, emissions, and hybrid or EV propulsion systems. These faults often affect drivability, performance, fuel economy, or emissions compliance.Browse powertrain subsystems: Engine & Powertrain · Fuel & Air Metering · Ignition & Misfire · Emission System · Cooling Systems · Transmission · Hybrid / EV Propulsion