That is the computer-controlled four-speed transmission. The place to start is by having any stored diagnostic fault codes read. They will lead you to the circuit or system with the problem, not necessarily a defective part. Many auto parts stores will read codes for you for free but most can only access the Engine Computer. You must find someone with a scanner that can access the Transmission Computer, also called the EATX, (electronic automatic transmission controller). The dealer's scanner and some aftermarket scanners will read the "clutch volume index" (CVI) which is a set of four numbers corresponding to approximately how much life is left in the four clutch packs. Be aware too that this computer learns the characteristics of the transmission and adjusts shift quality to provide nice smooth shifts with no slippage. That memory is lost when the battery is disconnected or run dead. It can take a few miles of driving or about a dozen shift cycles to relearn that. Until then it can shift like a race car or it can be very sloppy.
Sunday, March 20th, 2011 AT 9:44 PM