The light should come on when the fluid is over 300 degrees and a few other reasons. The fact it went away leads me to believe overheating.Letting it cool and then a few trips around the block won't be enough. You should pull over and let it cool for atleast 20 min. Then You can try a full fluid flush. Get this taken care of right away because before you know it the next time the light comes on your rpms will shoot up and the car will become a real pain to drive at medium speed for any time more then 10 min.
Just drop the pan and change out the filter, put pan back on-gasket should be reusable, put in 5 or so quarts, take the "cooler" line off and place in bucket, start car, watch until the new red fluid comes out, fill trans the rest of the way. I had an overheat on and off. I had to swap valve bodies though. Gaskets leak and and pumps get weak/break. The valve body contains the pump and solenoids. You could also have a stripped pump shaft. You could just have old cooked fluid in there. You wouldn't know until you get in there. Nothing looked wrong with mine, but I had low pressure that caused my overheat. The valve body is held on with normal hex head metric bolts. Drop the subframe a few inches. Take the trans mount loose, take that brace off, take all of those bolts out of the side pan, clean up the mess, clean up that mess too, shit there is more over there, screw it and take off the bolts that are missing in the new valve body, pull out valve body, pull out shaft and inspect, and then reverse.
I took the motor mounts loose to make it easier to move the motor over for clearance, but you don't have to.
If you do swap the valve body and everything else is good it will feel like a different car.
