Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2003 Saturn LW300, 2003 Saturn LW200, 2003 Saturn L300, and 2003 Saturn L200. However, it is still accessible from the selected car via links, so may be relevant.

The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
A scan tool can clear the MIL/DTC.
The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.