Suddenly the auto transmission has a hic-up and the transmission goes into a slip type mode - the message says "need of transmission service" the idicator light goes from "D" to "-". I stop the car - put the car in park - restart and everything is ok for a day to a week. then it happens again. When I hook up my plug in reader, I get the message that there is a Gear shift sensor fault. Do you think changin the gear shift sensor will do the trick?

 

What kind of car do you have?