On-Board Diagnostic (OBD) System

All 1996 and newer light-duty vehicles are manufactured with an On-Board Diagnostic (OBD) system. All manufacturers use the same type of connector, communication protocol, and trouble code-naming standard. The OBD system continuously checks the operation of key emissions control components and emissions-related systems. If a fault is detected that could cause emissions to exceed 1.5 times the federal standard, the dashboard MIL will be illuminated.