(Alt. Fuel) MIL Command

Display shows ON or OFF. The MIL (Service Engine Soon or Check Engine) is controlled by both the AF ECU and the gasoline control module (VCM/PCM or ECM). The (Alt Fuel) MIL COMMAND indicates ON whenever the MIL Control (AF ECU) output circuit is commanding the MIL ON. The MIL is illuminated if either module has detected a problem that affects vehicle emissions, driveability or could cause powertrain damage.