How m I sepose to know what is for what. All it does is when i turn the car on the wrench comes up and shows -200. Then turns off. One dealer said all i need is an oil change which they were charging $168 for a change. The other got this hole list they have to do which is going to cost $344 (includes flushing the trany oil, and bulshit checkups, but they charge only $75 for an oil change.. SO i dont know who to belive. Has any one done the first service and when and how much?