Regen question

[Nilao]

What jumps out at me is all 3 read exactly the same. That is impractical as you could drop those 3 sensors into a bucket of water and they'd all show a different temperature within a few degrees.

That -37 seems to me to be a default temperature. I'd definitely check the plugs for corrosion, the wires for evidence they were crushed/pinched or shorted together.