As JCL pointed out, and Killcraps SIB, the shifter LED is not a true indicator of the car going to sleep - if the light is on, and then it is off after 16 minutes of inactivity, then the car went to sleep. if the light stayed on past 16 minutes it does not mean it is not asleep - prior to 9/01 the WDS shows that LED wired in one way and after that date, it is wired differently. In reality we have established with the forum members that the date does not stand true, as some folks indicated a different behaviour.
And, after 16 minutes the car does not go completely to sleep, the GM module sends a "go to bed" signal and then some modules drop asleep and some modules start their internal countdown timer to go to sleep. when the internal lights are on, and/or the boot lights are on, they will remain on for another 30 minutes or after the "go to bed" signal and then will shut off... The car goes to sleep completely about 45 minutes after the last activity, as was stated before... the draw on the battery is minimal with alarm off, and about 35 mA with alarm on...
I understand that this will not help much with troubleshooting but at least will give an idea about electrical and electronic environment that you are working in - besides, JCL perfectly explained how to measure the amperage without disturbing the peace of the car...
