Finding the A/C clutch...

it would make a lot more sense if you told what make, model, year and engine.

"Proctologically Violated©®" wrote in news:lze8i.9$ snipped-for-privacy@newsfe12.lga:

Wouldn't you think...the clutch would be on the belt-end of the compressor?

Yeah, but I don't see any wires. The clutch is electrically activated, no?

You may want to start by just jumping the low pressure switch (easily shorted with a paperclip in a pinch) - it should be dead easy that way. I put my money on low gas or a bad switch. At least this quick test will let you know that you are low on refridgerant, have a bad dash switch, or you need a new pressure switch... or gawd forbid... something worse like a dead clutch or bad compressor. If that's of no use to you, I appologize but it has worked for me with every vehicle I've ever worked on (granted I'm a shadetree at best). Andrew.

in article OU49i.151$ snipped-for-privacy@newsfe12.lga, Proctologically Violated©® at entropic3.14decay@optonline2.718.net wrote on 6/4/07 11:38 PM:

Hey, shadetree's *are* the best! :)

Shouldn't I be able to find wires at the clutch? And where would I find the low pressure switch? And by dash switch, you mean the on/off switch, right?

I have found it pretty difficult to trace some circuits in cars. Worse, now, w/ boards'n'shit.

Well, I re-downloaded over 5000 message headers going back to March 3, and nowhere did I see you mention what car you're working on, so any help more detailed than "it's right there" will have to wait for you to spill the beans.

"MasterBlaster" > >>>> really is electrical by just putting a jump to the A/C clutch.

Toyoter corolla wagon, 1990, Honda Accord 1991. Also, for comparison, 1990 mazda 929S, altho that A/C is still working. But similarly on the 929S, the engine fan has an electrically operated clutch (I think!), and I can't find the wires on that, either!

On some systems you can see if the clutch is working. The inner part of the pully is stationary when the clutch is deactivated- you can see the center part begin to turn when the clutch engages.

"Proctologically Violated©®" wrote in news:Ua69i.82$ snipped-for-privacy@newsfe12.lga:

Why should you? The few I've looked at closely all have the clutch internal to the compressor and its drive belt pulley. The only wires are those in the connector block(s) for the compressor itself.

It really helps to have a good shop manual for the car you're working on. Do you have one?

As Tegger suggested, you will likely want to look at a shop manual or sorts for any detailed kind of answers. You may get lucky with:

If I were to take my best guess though... I would trace the piping from the condenser (behind the rad) to the evaporator (should be an aluminum 'soup can' looking thing (might be encased in plastic with a site glass). Anyway, there should be a valve on the low side of this evap with 2 wires on the harness. If you jump these two wires, you should effectively jump power to the clutch. As for the dash switch, yes, I meant the in-dash AC/FAN or similar switch. The relay that controls the compressor usually feeds both from the low pressure switch and the dash switch. More aften than not, your problem will be found easily by checking both of these circuits. As for jumping the compressor clutch directly, I have never found any need as I always use the low pressure switch harness first. I would imagine it would be easy enough to do though to test the harness that comes off the clutch for +12V, GND and maybe a reference wire. Again, Tegger's advice to consult a schematic in a manual is very good advice indeed. There's no substitute for looking at the proper schematics. Good luck, Andrew.

in article Ua69i.82$ snipped-for-privacy@newsfe12.lga, Proctologically Violated©® at entropic3.14decay@optonline2.718.net wrote on 6/5/07 1:06 AM:

"Proctologically Violated©®" wrote

http://67.129.153.73/CGv2Production/Pictures/Honda%20J-Pegs%5C38810Pt0013.jpg

coil in the middle controls the speed.