No A/C. Not cool.

[NKent]

So I got my '92 about 3 years ago and I finally put in a new A/C compressor since the old one had a crack in the side of it. I got the new one on there in short order but it will not turn on. No matter where I put the switch (normal A/C or max A/C) the clutch is not engaging the compressor. I tested the little 2 wire connector at the compressor and neither wire is getting power. I followed the wires back a foot or so to a large connector, still no power to the wires before that connector. Fuse is good, fan comes on but blows no cold air. Do I need to rip into the dash and check the switch? I hate interior work.

 

[JDiepstra]

I don't know, but that "No A/C, not cool" title made me laugh!

 

[BHerring]

Ok here,



How or who charged your system.



I know it must have a min. charge for the compressor to turn on.



let me know

 

[Greenleaf]

Dude! CHILL-OUT!



Anyone else think that was funny..... hum??



No matter. The relay man. The RELAY. It be the one closest to the hood hinge. It has battery power. Then it has a ground wire and a signal wire (from the a/c system switch) and a power out wire to the clutch. If you jump the bat wire to the power out wire OR jump the bat wire to the signal wire the relay will engergized if its good or be bypassed depending on how you give it power with a jumper wire. Thus, you test the relay and everything downstream.



The in cab wsitch is tested there too bt looking for pwer at the signal wire.



The terminals on the relay should be numbered.



86 is the signal, positive in this case I believe.

30 is battery power

87 is power out to the clutch

85 is ground for the signal circuit



There is also a low charge cut-out switch. Low charge= no compressor power



And to complicate more, there is a evap. temp switch that could be bad.



You have the factory manual, right!?



You got work to do.



You charge it with HC12a? (ref grade propane)

 

[NKent]

still hunting

I took the dash apart and the switch is good. There is continuity from the wire out of the switch to the compressor. I have to test the vacuum line but other than that all that is left is the temp control switch. It will be in at the local dealer tomorrow. I got a full printout of the A/C system from them and that is the only switch it has. No high pressure/low pressure cutout switch. Only the temp sensor. Any ideas on what the vacuum line from the booster to the condensor should be reading? I'm gonna tedst that tomorrow before I drop $80 on the switch.



I am filling the system myself with the cans of r134A and the little parts store regulator if that matters. I put in 1 can on the low pressure side until it read 65psi and the comp did not kick on.

 

[Greenleaf]

Is this a factory install system? You will have a relay on the driver side fender well and the low pressure switch is located right on the side of the expansion valve, right up against the fire wall where the pass side fender well meets the far end of the fire wall. Very tough to get to. You can, with small hands, remove that plug and bypass this switch with a jumper wire.



I don't know what a "booster" is so cannot comment on the vacuum line you speak of.



The temp swith can be tested by removing the temp probe wire and bypassing that. I really would not buy a switch to see if that fixes your problem. The manual gives meter reading at specific temperpatured to test the temp sensor. I'd have to look that up for you in the book.

 

[BHerring]

charging the system, I have charged my Dodge system twice and my other cars... anyways. to do the job rigth you must put a vacuum on the whole ac system, once you have a good vacuum and it holds steady, then when you hook up your can of r134a it should suck it in completely and usually that is enough to get the compressor to turn so you can charge the rest of your system...



to get any R134 into the system the Compressor must be on... .



Now, with that said, you can charge the system without putting a vacuum on the system, the compressor must be on to charge the system. I suspect the reading you got was in error.



FYI, must cars and trucks that I worked on, I must have a full can of R134 or R12 for the compressor to stay on.

 

[NKent]

Chillin'

So, I still have not found the ghost in the wires. The guy in the parts dept. came out to the lot and put a new temp switch in for me and when it still didn't fix it he put it back in the bag and did not charge me for it. They ordered the relay for me but it will not be in until next week sometime. I wound up running a switch from the compressor to my dash via the fuse box so I have an on-off for now. That will make my 3 hour drive to colorado springs tonight much more pleasant. I had a local mechanic charge the a/c system and it is blowing 46 degree air. That kicks ***!



Thanks to all for the help and advice!