Stuck in 3rd gear after Transgo Jr install

[unit]

I put a Transgo Jr in my 6 speed Allison today and had an issue with a broken solenoid wire. Got that fixed, put everything back together and went for a test drive. The trans shifted hard once and went to 3rd. gear and stayed there. I don't get any other shifts. Reverse works fine. I pulled the codes and have only one, P0972.

I posted earlier about a wiring problem and fixed that. I'm kind of wondering if that repair might be the problem. The attached photos show the details. I pulled the wiring harness from the trans and fixed the connector by soldering the wire to the pin. It seemed to be a good connection but I wonder? The connecter is the one above the row of other connecters and is partially hidden from view when looking up at the valve body while it's still in the truck.

Photos of the wiring problem are attached in case they might be useful.

All help is appreciated!

 

[Mike L.]

Check the connection at the upper most solenoid. The one that is hard to get to after valve body install.

 

[unit]

Thanks Mike. I can pull the pan and look at it and ensure it's snapped in correctly. Anything else I can do to check it?

 

[unit]

Pulled the pan and checked the connector on the upper most solenoid and sure enough the wire was loose again. I've resoldered the wire and will try again. Thanks for the help Mike!