MainePorsche

Best wishes.
Hope it's the quick and easy.

chitown928s4

Jumper the clutch wire to the 14 pin post to see if you can get the compressor to turn on. If if does your relay from the hvac head unit doesnt have enough power to turn compressor on.

StratfordShark

If you do that test checking for 12V at the freeze switch, then you can't assume the relay in control unit is ok unless you put a load (like a headlight bulb) between freeze switch and ground point and can confirm voltage does not drop dramatically.

When the relay fails it may pass small currents (a decent multimeter will draw less than 1 milliamp when measuring 12v), but tyere will be a big voltage drop when you demand current similar to the compressor load.

Your problem is either:

relay in head controller
corroded contacts in freeze switch (happened to me - easy fix)
Seized compressor/burnt-out electric clutch

Keep us posted!

marinesniper0318

Well I tried jumpering the freeze with, I basically disconnected both and jumpered a cable between them, then tried the AC again and nothing, I see the RPM drop when I press the AC button but no cold air still...now I need to jack up the car and check the power connection to the AC compressor...

Any other possible easy ideas to try ; )

thanks...alot brothers...!

Sniper

PHIL928

if the rpm is dropping then the AC clutch is engaging.

MainePorsche

Yes, check that. But also check the singular black wire that comes off the wire harness that runs across the front of the engine. This feed to the compressor exits the harness just above the belt to the air pump and is slightly medial to the R distributor base. This wire often gets 'bothered' by work in that area. Also, if not properly secured the accessory belt can damage it.

MainePorsche

BTW, did you get a voltimeter to the freeze switch wires ? This would be telling to us all.

MainePorsche

Most novices will mistake the pulley turning as the 'AC is on'.
I'm betting the clutch is not engaging, and the perceived rpm drop is spurious.