Malfunction Indicator Light (MIL)
WARNING: This page is about a different car, the 1992 Mercedes-Benz 400E. However, it is still accessible from the selected car via links, so may be relevant.
The MIL receives voltage from base module. Base module is color-coded Black and located in module box in right rear corner of engine compartment. MIL is illuminated through a ground signal form the diagnostic module. When ignition is turned on and with engine speed up to 500 RPM, MIL is illuminated for a maximum of 30 seconds as a bulb check. If no malfunctions are present, the diagnostic module opens the ground to MIL, causing MIL to go out. See Fig 1 for component locations.