On-Board Diagnostics

When an abnormality occurs in a signal from a sensor, or when a problem occurs in one of the systems monitored by the Electronic Control Module (ECM), the ECM lights the Malfunction Indicator Lamp (MIL) and stores the Diagnostic Trouble Code (DTC) in erasable memory. When the ignition is initially turned on, the ECM lights the MIL for two seconds to test the bulb.