transmission light just started comming on after about 15 minutes of cold start
 

2000 discov 11 116k no problems, red light came on for the first time i think(overheated transmission) somes times comes on and then goes right back off. temp here is 100 plus every day. had the transmission and filter serviced, i watched them do it. actually pretty clean. still does the same thing. transmision shifting acts normal no slippage. this seems to be a pattern every day. transmission comes up to temp in approx 15/20 minutes, light goes off and on a few times and then says on untill you get on the open road for several miles and then it sometimes goes back off, sometimes it doesnt.