My check transmission light came on right after the car hit 120,000 miles. I had been driving the car for about 2 hours on a highway. I did not experience any problem until I got off the highway. At that time the car seemed a little sluggish when changing gears. When I turned car off and restarted car about a half hour later the light went off and the sluggishness disappeared. Any suggestions?? Thanks!!
I strongly suggest that you have an independent transmission shop check the status of your transmission. Cars are not normally known for healing themselves, and while the warning light might have turned itself off, the condition of the transmission is something that you should be concerned about–especially if the fluid and filter were not changed every 30k.
Note: I assume you have already verified that the transmission fluid is at the proper level and that it has both a normal color and a normal odor.