Chrysler Repair: 95 Cirrus transmission limp mode: 2-4 solenoid, obd ii connector, master mechanic

Question
I've read several posts from several sights talking about the same exact "ghost in the machine" problem I am having but none of them give a definitive answer for what the root of the problem is. I bought my cirrus from a retired chrysler master mechanic with 27 years of experience who replaced the transmission for a guy but ended keeping the car and selling it because the guy didn't want it back. And I can't blame him now that I've had it and am dealing with it dropping into limp mode at random times. Sometimes it will be fine for 2 weeks, and then sometimes on my 2 hour drive to the city it will do it 8 times. Which is all kinds of fun because at those speeds it just goes to nuetral. I took it back to him and he hooked it up to his big scanner and it read out that the 2-4 solenoid was bad so I bought a new one and put in myself. But just like every post I've read said, it didn't solve the problem. I read one that said to put a new ground wire directly from the negative post on the battery to a bolt on the solenoid or any where on the transmission and that will fix it. I just found that today am going to try that but wanted to know if you have ever heard of a "for sure" solution, or even what the real cause is.

Answer
Hi Chris,
The transmission has a ground location with a wire attached to it, at the rear of the transmission towards the firewall side. If you would take a look at that wire and see what it is attached to at its other end and let me know I would be most appreciative. The battery ground point is the left strut tower, and I wonder if that might be the place where the wire on the trans goes to (the manual is not clear about it)? Were they both grounded there then it would be a matter of checking for clean tight connections at all three points.
Did you replace the solenoid/pressure switch pack as a whole, or just the 2-4 solenoid?
In the '05, do you have an OBD-II connector to link to a code reader, or is it the 6-pin Chrysler data link connector? One way or the other I would try to get another readout of transmission fault codes.
The 2-4 solenoid circuit is connected from pin 8 of the pack to pin 19 of the tcm so you might want to check that for continuity. If goes through a 10-wire disconnect that is gray in color located under the power distribution center so check out that connect/disconnect interface (wire is white/pink on one side and white on the other side of the disconnect.
I will be curious to know what you learn.
Roland
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