AC & Heater Switch Overheats/burns up/??RELAY SETUP

[stringpickin]

Hey and Good day!

I dont't know about you, but it seems like I have to replace my AC/Heater Switch about ever 2 years. It dies the same way every time. It gets hot, I smell that favorite electrical stuff is burning smell, and zap the fan quits working. I learned many years ago, don't reach under the dash and grab the Plastic Wire Plug that plugs in to the AC switch right as this happens. It burns like 60.. I once could see smoke coming from there and new what was happening and thought might start fire, so I tried to yank it off. Don't Do that unless you absolutely have too..

What is strange is it never burns the fuse out. The switch goes first.. And also it does actually destroy the actual contacts of the switch because it gets sloppy when you flip it up and down afterwards..

So....Anyway.... Anyone else have that problem? I have heard a couple of people tell me they have that I have talked to here and there on the street.

That leads me to the question. Has anyone here come up with a slick and easy way to wire relays in to the system so that the juice of the Fan Motor and the Compressor Clutch so that the AC switch is only used to throw the relay and the juice runs through the relay for the two???

I am sure I can figure it out eventually, but I was hoping maybe someone here could help me out, save me a bit of time and give me some good advice on what they found as they accomplished it.

Or maybe there is another fix that is out there because something else is causing this problem that I for the life of me cannot seem to figure out?

In either case, I would appreciatte your help, advice, and time..

Thank you very much. If you want to post here, that is fine, but if you want to email me at stringpickin@sbcglobal.net that is fine too..

Moderators. Please bare with me as I post this same topic to the Blazer section, and any other section that includes this same AC system so that I can possibly hit someone that can help. Thank you.. String..

[pound41]

When I bought my 70 blazer a few years back It was obvious that it had the problem that you have.Also some wires had gotten a little hot and were brittle. They had various toggle switches set up to run the ac and heat. I put a new ac/wire harness. LMC at the time they were something like $20 cheaper than everyone else so I did it. Never have looked back

[blazerparts]

There should be a fan relay installed if your truck is a stock AC truck ( relay is behind glovebox. If your truck was not originally an AC truck and upgraded with a AC fan and no relay was installed that might be your problem.