Diagnostic Test Mode I
WARNING: This page is about a different car, the 2002 Infiniti QX4, 2001 Nissan Pathfinder, and 2001 Infiniti QX4. However, it is still accessible from the selected car via links, so may be relevant.
As a bulb check, MIL glows when ignition is turned on and engine is not running. When vehicle is started, MIL will turn off, indicating that no malfunctions are detected. If a malfunction is detected while the engine is running, the MIL glows or flashes and a corresponding DTC will be set in ECM memory.