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Ralph Mowery

In article ,
says...

It should be possible to find the source of the problem with the OP's
car. You're right, today many alleged mechanics are incompetent.
I have a friend who had a Honda CRV. The AC didn't work, he had
taken it to shop that specializes in AC. They spent hours, told him
they couldn't find the problem, they thought it was an electrical
computer thing, so they took it to another shop that specializes
in that. They also couldn't fix it. I said bring it over here,
let me look at it. I had him put on the AC and I took a look at
the clutch. It wasn't spinning, so I probed it with just a test light.
Voltage at the clutch. I got a hammer, tapped the clutch a few times,
had him try it again. Voila, AC working.

That one is so basic, it boggles the minds how any shop that does AC
work couldn't identify and fix it. He kept the car for another couple
years after that, no more problems with the AC. I did instruct him to
run the AC once a month on moderate days, just to keep things moving.

It is good to run the AC once or twice a month even if you do not need
it.

It is interisting how those mechanics can not seem to do basic trouble
shooting before looking into something complicated. One would have
thought like you did. Look at the compressor to see if it is turning.
If not, check for voltage. If voltage, look compressor, if no voltage,
look for something more compicated like a blown fuse, or a low pressure
cut out switch indicatine most often low refregerent.

Always do the very basic simple tests first unless there is a known
history of a certain failed part.

Where I worked it never faild to surprise me how many could not catch a
blown fuse. They could not get it in their heads that in some circuits
(mostly 3 phase) that you could have power on each side of a fuse and it
still is bad.
Some control circuits had low value capacitors across the switches. They
would pass enough voltage to light up the simple neon testers many used.

I really loved the tester I used most often. It had two leads and a
row of LEDs. YOu could put it across anything from about 20 volts to
600 vots. Look at the leds. If there was voltage above 20 volts a led
or more would light up indicating if low voltage, 120, 240, 480 volts.
Another for DC. and another is low resistance.