Control valve block
Trans. ground wire
Shift Solenoids
Speed sensors
Definitely not TCM issues even though there are conditions that cause you to have to get it flashed like with the ECM/TCM

P0792 is just a top-level error for internal trans. issues. P0734 is the more specific sub-level code. Get a TCM scan at a trans. shop for $40-$100 to get way better details/codes.

Things you can do without a pro:
Change speed sensors(2 of them)
Change ground wire
Change valve block
Change filter, o-ring, fluid and clean magnet and pan
Try Lucas treatment

Worse case scenario: Wiring issues(this was really only an issue with 3rd gen and older) around TCM or you need a rebuild. The good Mopar kit is around $400.00 if you know someone who can do it.

 

UPDATE: I took my T&C back to the dealer (after the transmission rebuild) to have them solve this mystery problem. They had it for 1.5 weeks and could find nothing but the wires I had bypassed during my troubleshooting. I had them rewire the sensors and they then suspected the TRS(Transmission Range Sensor) switch because of the instrument cluster indication. They asked me if the Compounder was replaced during the rebuild and I informed them that it was rebuilt but not replaced. They then pull the side cover off to look at the TRS and wiring. When the pulled the cover they said that they found chips in the pan and that it looked to be coming from the Compounder. They siad the the wiring looked ok and gave me an estimate for a Compounder inspection. I called my transmission mechanic(He rebuilt this trans) and he suggested that I bring it back to him because, "you hired me to do the rebuild and I should complete the work". That kind of integrity is rare nowadays, but I digress. My trans mechanic pulled the pans and could find no evidence of chips or fuzz. He proceeded to pull the tranny and go through it to ensure no contamination existed. He then pulled the Compounder out and apart and it looked like new. He mic'd out all the components and checked for warpage but the compounder was perfect. He had another rebuild kit in his shop and he rebuilt the compounder for a second time, just to be sure. He put it back together and replaced the TRS while re-assemling it, to fix the boxes around the trans position indication on the instrument cluster. (the indication problem started after the transmission rebuild, so my trans mech said he would replace that part antway as he did not catch that problem when he test drove it after the rebuild) When he went to test drive the van, the boxes around the indicators were still there. A little frustrated he went back through what he did on the original rebuild and he noted that he had replaced the solendoid body as a possible cause for the transmission codes(P0734 & P0792) I had been getting. Since all the signals from the TRS go throught the solenoid body connector he put a new solenoid body on my transmission and this fixed the indication issue. he then test drove the van and the P0734 & P0792 codes did not reappear. He drove the van for 10-15 mile with no problems (these codes would set within 5 miles everytime before). I picked the van up on Christmas Eve and it has been working great for the last week. So it looks like the P0734 & P0792 codes were corrected by the replacement of the TRS. As unlikely as that sounds, it is the only part, that was changed, which caused a change in the trouble codes.
If the TRS was the problem then I wonder how many remanufactured transmission were replaced for this simular issue, as a remanufactured unit would have a new TRS installed?
$4000.00 fix for a $30.00 part?
I am just happy that my T&C is back on the road and I will update should this problem rear it's ugly head again