Smart box question

[Gcelevator]

Hey guys, i know this subject is a beaten to death Horse, but the way my smart boxes are behaving are a little weird.
So my temp sensor went out 1st (didn't have the chance to replace) and then the samrt box started behaving weird. Wait light not turning off and AC not turning on. By turning the ignition switch several times on and off eventually the AC blower turned on and that's how i know the wait laight will turn off.
For the record, this is a yellow label nortron box.
Decided to use a look like new box that came with my 1151 (unsure of condition) and a new temp sensor. After installing everything worked flawlessly, went on a 300 miles trip and upon return the wait light does not turn off at all. This time the generator is not charging at all.
The board and components on both boxes looks good with no visible damages, what leads me to believe that the big round relay might be the culprit and once again, i might be totally wrong. Pictures attached.

I also have a KDS white label box that apparently have good components, i might try that one next with the correct temp sensor.

What is the preferred type of smart box (besides CAmotech) or more modern that has least issues?
Also; by what is going on in my case, is there anything else that might damage the smart box?

Any suggestions? Thanks.

 

[NDT]

Suggest you carefully inspect the Cannon connector that is in the engine compartment that plugs into the start box. Water gets into it and causes corrosion between the wires and pins that can lead to intermittent connections.

 

[TOBASH]

Check the link in my signature line. That integrated circuit causes more trouble than it is worth.

 

[Retiredwarhorses]

Any other box other than an S3 is garbage, the yellow label Nartrons are notorious for stuck GP timers, if that light is on? You are getting
voltage to the GP’s…and that’s not good. You didn’t state what model truck you have…
edit: TSU’s are backwards compatible, the sign of a bad TSU is fast flashing wait lamp, other than that, it causes no issues like what you state, you can leave it unplugged and operate the truck, it’s a temperature sending device.