Welcome back man, you went missing for quite a while, by the way, if you are interested, I could add your name here >
https://bitcointalk.org/index.php?topic=5297994.0, you are the most experienced member in fixing these hash boards, trusted and can probably do better than most of those overpriced services listed, check it out and let me know.
I have an issue with my T17, one just 1 hashboard. Sometimes i get 0 asic found sometimes it finds all 30. But in any case, I get the error for all temp sensors on the board. I think I've went through most of the posts here and it most likely resembles the issue I quoted below. As I could see, most likely its loose heatsink, but after my (inexperienced) inspection, none seems loose when tested with mild pressure.
It's more like a bad chip connection than just a loose heatsink, in fact, if the heatsink isn't shorting anything, the miner will still run for a very short while before showing "Over-Temp", but getting the temp sensors errors is probably because of a dead/burnt chip or a bad connection between one of the chip and PCB.
This problem could also be caused by a bad PSU, do you have another PSU to test with?