I can't add anything good, but I can make some comments that may be helpful later. Steve uses the same logic as I do when there's multiple fault codes.
If you want to access an online service manual, we use AllData. Shops pay about $1000.00 per year for access to all models. You can buy access to just your one model for about $28.00 per year or $49.00 for five years, last time I checked. I can post diagrams for you too, but they purposely made copying them difficult. To get acceptable clarity, I have to expand them, then copy them in multiple pieces, and then group them together to make them readable. I do this all in MS Word, a typing program where I can add callouts and arrows. I know there's easier ways, but this lets me manipulate them later, if needed. From there I copy them into MS Paint where they can be saved in a JPEG format that can be uploaded. I did that for all of your fault code diagnostic steps until 6 a.M. This morning. By using MS Paint, I have to do them all one page at a time, so some have over 20 pages to read through.
One thing that made this easier was the procedure for diagnosing three of the codes, while 21 pages long, are almost identical. I had to read through them and just change a few numbers here and there. I'm going to post the steps for one of them for now. Since almost everything is the same, if you find the cause of this problem with the steps for one code, you'll likely solve all the other codes at the same time.
Steve alluded to something I was never taught in my TV Servicing class, but I did learn it years later. That is when it comes to a "black box", meaning a module, a computer, or an integrated circuit where you don't know what's inside, you need four things for that box to work. You gotta have all the power supplies, all the grounds, nothing is open or shorted on the outputs, then you'll get the proper outputs if the box is okay. It's common to have four 12-volt feeds to the Engine Computer. One is constant to maintain fuel trim numbers and learned sensor personalities in memory. One is switched on with the ignition switch to turn it on. The computer turns on the automatic shutdown, (ASD) relay which powers up the injectors, ignition coils, and a few other circuits including one that goes back to the computer as proof it got turned on. I don't remember where the fourth one came from.
I already described the multiple ground wires. It appears you already verified the 5-volt sensor supplies and the grounds are okay. I would have suggested the same thing Steve said about the unlikelihood of so many failed sensors, and to look for what they have in common.
One thing that didn't come up yet is problems with the TIPM, totally integrated power module, (under-hood fuse box). Most people think those cause a lot of trouble, especially from corroded connector terminals on the bottom. I have a friend with a repair / body shop who specializes in rebuilding smashed one and two-year-old Ram trucks. I get called when he has electrical problems, and since he often is the owner of these vehicles, I've had the opportunity to take some of those modules apart. One had an intermittent no-crank problem, and to learn how the system works, I took the TIPM apart. To my surprise, there were only 13 relays, a lot of fuses, but absolutely no electronics inside it. That's why you'll often hear they're "plug and play" with no programming required. It just had seven or eight layers of metal with fingers bent up to form terminals that plugged into other layers. It's easy to find these in a salvage yard. Go by application and check that the same fuses are in the same locations. The modules can have different part numbers.
My reason for bringing this up is you might consider connecting your voltmeter to these 12-volt lines, one at a time, and watch if they hold steady. If one flickers or has dropouts, try wiggling the connectors under the TIPM to see if that changes anything.
Now, to add to the misery, some TIPMs do have a small module plugged in on the driver's side. If you plug the old one into the new TIPM, it will work fine. If you install a different one, some functions do work, so you can drive the truck to the dealership, but they do have to reprogram it to that truck for everything to work.
I'm going to split these diagnostic steps up into separate replies to lessen the confusion. Here's the simplest one. It's for code P0600.
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Tuesday, January 23rd, 2024 AT 5:58 PM