what to do?

I own a 99 grand caravan 3.8 awd that about a month ago went into limp mode,after playing with wires and tightening the plug on the tcm it fixed itself. About 4 or 5 days ago it went into limp mode again and I changed the output and input speed sensors and that didn't work so I currently have purchased a remanufactured tcm but have not installed it yet.Both times that it has done this it has been rainy/snowy and cold so I am wondering if it could just be a bad ground but do not know where to look for the ground. also my manual says that I need to a transaxle quick learn procedure if I change the tcm and would like to know if this is something I can do myself or if I have to take it to a shop? any help with either of these would be very greatly appreciated.

Thanks

o.k. I found the ground and cleaned real good with a wire brush it was actually in pretty good shape so now all I need to know is what will happen if I don't do the quick learn procedure and if there is anything else I should do when I change the tcm

Where is this wire at?

The one I found is bolted to the head just under the front valve cover.I'm still not sure if it is the right one but it was worth a try. now as soon as I find out if I have to take it to the shop to do this quick learn thing or if I can do it myself I will change the tcm

The one I found is bolted to the head just under the front valve cover.I'm still not sure if it is the right one but it was worth a try. now as soon as I find out if I have to take it to the shop to do this quick learn thing or if I can do it myself I will change the tcm

I have a '92 3.3L and she has 3 ground wires. The one you mentioned is the battery -wire, there is one on the trans and another on the left side engine mount to the body (the alternator side of the engine).
All the best.