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Sheesh... I'm definitely feeling a little backlash from the continuum here! Now my air conditioner has quit working. (And in Florida, that's serious.) If I didn't know better, I'd think the Beastie was ticked off at me for neglecting it over the past few months. That's what I get for coming out of retirement and getting a stupid job.
This A/C thing has me stumped and I'm hoping for a little troubleshooting advice. Here's what I know so far:
The compressor doesn't come on when I hit the A/C switch. However, the radiator cooling fans come on normally and the idle adjust bumps the idle a little to compensate for the load... just as if the A/C were running. So those parts of the circuit appear to be normal.
There's plenty of freon in the system, hoses are only a couple years old; I don't think there are any leaks but I haven't checked with a sniffer. The sight glass is clear... but of course, I can't see what it looks like with the system running right now. I checked it back in December and it had a tiny fine stream of bubbles, indicating a good charge.
At first I was afraid I had a bad compressor clutch, but that isn't the problem... the compressor is not getting power. I put a voltmeter on the red wire going to the compressor, and there's no voltage there when the A/C is switched on.
I thought, well, maybe the system =is= low on freon, and the pressure sensor over on the filter/drier is kicking the compressor off. So I shorted the leads to the pressure sensor to see if I could get the compressor to come on. It didn't. Again, low freon doesn't appear to be the problem.
There's also a microswitch on the throttle body that's supposed to kick off the A/C when you're at or above something like 70% throttle. I wondered if that got stuck during a turbo boost test recently? I moved the throttle butterfly by hand and thought I heard a faint little "tik" inside the switch, so I'm presuming it's making and breaking contact inside, but I didn't do a continuity test to verify.
Looking at the schematic for the A/C electrical system, I got a bit confused. It shows two relays for the fans, and the various pressure, temperature, and throttle microswitch cutouts. I tried to trace the wiring from the compressor, the single red wire goes into a wire bundle and I can't figure where it comes out. There are two fuses for the system, and both are good. I don't know how to test those two relays, but the fans come on as they're supposed to, so they appear to be working.
I'm stumped. Why isn't there voltage at the compressor when I press the button? Can anyone advise on where I should look next?
Time to go jump in the pool to cool off.... thanks in advance for your help.
- = M = -
posted by 208.63.2...
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