Code U0101, check engine light on?

Hello, this code points to a loss of communication between the engine computer and the transmission computer. This can happen for a number of different reasons, there can be a connector issue at the transmission computer (TCM), there can be a corroded connector or a section that is causing bad communications when it gets hot. Do you notice the transmission drop out at any particular time or after a certain amount of driving time? Maybe after being on the highway. The communications network between the modules in the vehicle is much like an internet network, except the modules are all hardwired together. I'll look for any Technical Bulletins on this issue and check to see where the transmission computer is located.
When the transmission drops out, do you lose all drive gears?

The transmission module and engine control module (PCM) are one unit in this vehicle and there are a number of PCM software updates that are posted as Technical Service Bulletins, they have to do with adaptive learning values. So, for example, the PCM will eventually learn the best shift points and speeds for different conditions and the way you drive as well as normal transmission wear over time.
The fact that you can restart the vehicle and it drives ok after that, sounds like there might be an issue with the software and when you restart the engine it might be resetting that memory. I will post some of these TSBs. You can also check the main connector on the transmission but there are no communications between the actual transmission itself and the engine computer, since all the transmission outputs come from the engine computer. So stopping by a dealership and seeing if they will run any software updates would be the first thing to check, but Ill post some of these software TSBs so you can print them out if you want to.

Do you know if you have any over the air update systems or subscriptions in place? This is where you would get software updates over a Wi-Fi connection automatically
And are there any other codes set?
It is also possible another module is failing intermittently and pulling down the network communications. These are not easy situations to give a definitive answer to because of so many possibilities. But go through all the fuses in the vehicle and make sure they are all tight and plugged in fully. There is a fuse panel in the engine compartment and one on the driver side under the dash.

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Okay, no, I wouldn't replace any modules at this point. Now that you have another new code, this points to a wiring issue or a different module disrupting the canbus network. I was doing some research on your vehicle, and do you have a rear camera that comes on when you put the vehicle in Reverse? I'll check the wiring diagrams for the IAT sensor and that code. Let me know on the back up camera option.
The TCM looks to be part of the PCM, so they are one module. And a different module sending out bad data packets can cause network codes.

Okay, the Intake Air Temperature sensor is part of a multi component sensor, it has a MAP (manifold absolute pressure), MAF (mass air flow) and the Air intake temperature sensor all in one. It's a 4-wire sensor near the throttle body. Do you have a scan tool that can read live engine data? If not, we can do some voltage checks at the sensor itself, it's pretty straight forward verifying the IAT sensor has the correct 5volt feed. It's just a matter of unplugging the sensor and turning the key on, engine off and touch one of the pins on the connector with the other meter lead on Battery Negative post. If you're okay with testing, you don't want to replace a possibly very expensive computer just to find out its a shorted wiring issue.
When you unplug the sensor connector, testing is diagrams 2, 3, 4, 5, 6. With the Key On, engine Off just check for the 5volt Reference feed first on the green wire of the 4-pin connector. You can use pin 4 (black wire) for a Ground if you want, or Battery Negative.

Since no other codes have set for that sensor, I think the Ground for it should be ok. If the 5volts is missing, that is a concern, and we will have to go to the PCM and check the connector for any corrosion. That might also be causing the U code.

Now if you want to go right to the PCM and check the connector for any corrosion or pin issues you can do that first too. You might find that is the root cause here for the other issues, diagrams 7, 8, 9, 10 are the PCM location and the connector C44-K which is the larger of the two connectors, You don't need to remove the PCM or anything, you can make sure the key is off, doors are closed, and disconnect that one connector and check it for corrosion.
Check that MAP sensor connector first for 5volts, it's also possible since the PCM U and P code are showing up after things get heated up, it can definitely be a PCM connector issue or solder joint. Considering where the PCM is located. I don't know why they keep them is location where they're prone to failure.