Automotive Diagnostics Glossary
Definitions of terms related to check engine codes and diagnostics.
Diagnostic Trouble Code - A Diagnostic Trouble Code (DTC) is an alphanumeric code generated...On-Board Diagnostics II - On-Board Diagnostics II (OBD-II) is a standardized automotive ele...Powertrain Control Module - The Powertrain Control Module (PCM) is the primary onboard comput...Engine Control Unit - The Engine Control Unit (ECU), sometimes called the Engine Contro...Oxygen Sensor - The Oxygen Sensor (O2 Sensor) is an electrical component mounted ...Catalytic Converter - The Catalytic Converter is a critical emissions control device in...Mass Air Flow Sensor - The Mass Air Flow (MAF) Sensor is an intake system component that...Limp Mode - Limp Mode, also known as restricted performance mode, is a failsa...Freeze Frame Data - Freeze Frame Data is a digital snapshot of engine operating param...Readiness Monitors - Readiness Monitors are automated self-diagnostic routines evaluat...