Conditions for Clearing the MIL/DTC

The ECM turns OFF the MIL at the beginning of the fourth ignition cycle, after 3 ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC and related Freeze Frame data clears after 40 warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.