2000 TC Transmission Issues

2000 T+C goes into 'limp mode' every so often (has been getting more frequent) and CEL comes on. Usually shutting the car off and starting it again will solve cause it to shift normally again until it gets triggered the next time.

Took it to a local Chrysler dealer and they said it threw codes related to the transmission oil switch and some sort of solenoid, but said those parts "looked fine" and quoted a new transmission. Anyone here familiar with these cars and what could be the issue here? It's been shifting fine when it works and since none of the codes seem related to the transmission itself from my research, I'm not entirely sure a brand new transmission is needed. Any advice would be appreciated.

 

I got the full report from the dealer. They found the following codes: p0731, p1784, p1776, and p1700. They also noted the the fluid was "slightly burned" but the level was good and there were no metal shavings or anything in it. I never had the tranny flushed at the service interval (current mileage ~120k) because the tech at my last dealer told me if everything was working fine, it was better to leave the existing fluid. Any thoughts on any of that?