Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2005 Cadillac STS. 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 default actions when the ignition is OFF long enough in order to power down the TCM.

DTC P0727

Step	Action	Value(s)	Yes	No
1	Did you perform the Diagnostic System Check - Vehicle?	-	Go to Step 2	Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2	Install a scan tool. Turn ON the ignition, with the engine OFF. IMPORTANT: Before clearing the DTC, use the scan tool in order to record the ECM Freeze Frame and the TCM Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM and the TCM. Using the Clear Info function erases stored DTCs in both the ECM and TCM. Record the DTC Failure Records. Did you record any ECM Failure Records?	-	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	Go to Step 3
3	Did you record a TCM Failure Record for DTC U0100?	-	Go to DTC U0100-U0299 in Computer/Integrating Systems	Go to Step 4
4	Clear the DTC. Turn the ignition OFF for at least 30 seconds. Start and idle the engine. Observe the Engine Speed on the scan tool. Is the Engine Speed within the specified range?	500-1,000 RPM	Go to Step 5	Go to Step 6
5	Road test the vehicle using various engine speeds. Did DTC P0727 reset?	-	Go to Step 7	Go to Intermittent Conditions in Engine Controls - 3.6L or Intermittent Conditions in Engine Controls - 4.6L
6	Select Engine Data on the scan tool. Observe the scan tool Engine Speed parameter. Is the Engine Speed value within the specified range?	500-1,000 RPM	Go to Step 7	Go to Step 8
7	Did any other DTCs set?	-	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	Go to Step 8
8	Replace the TCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Is the action complete?	-	Go to Step 9	-
9	Perform the following procedure to verify the repair: Select DTC on the scan tool. Select Clear Info. Turn ON the ignition with the engine OFF. Operate the engine at varying speeds. Select Specific DTC. Enter DTC P0727. Has the test run and passed?	-	Go to Step 10	Go to Step 2
10	With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed?	-	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	System OK