3Js

When turning on the AC on, should the dual electric fans automatically come on?
Also, if the compressor isn't cycling will the fans turn on when the AC is turned on?

tech2

#1 yes, fans should turn on with a/c...if they didn't the system would quickly overpressure when the vehicle is not moving.

#2 probably not...the compressor is engaged by a relay controlled by the pcm. if the pcm see's a fault and inhibits the compressor...it may also inhibit the fan for a/c but would allow fans for a coolant temp hot condition. A fan fault will not inhibit ac. the a/c will run with no fan...until it overpressures...then the high pressure switch will open and shut off the compressor.

What is the problem you are trying to fix?

3Js

"What is the problem you are trying to fix?"
https://chevroletforum.com/forum/tah...tent-c-102027/

AC system is empty. Should be at normal atmospheric pressure since I opened the system to check orifice tube condition.

So I drove the truck today on the freeway. Two ways for about 25 min. each at 65-70 mph. Ambient temp about 99*. Temp gauge just a line under 210*.Where it normally runs.

When I got to the first destination I popped the hood. No electric fan running. Turned on the AC. No fans.
Second destination..same thing. No fans,

3Js

I disconnected the coolant temp switch and the fans came on. Is this the default condition?