Another AC question

Topic: Another AC question (Read 1556 times) previous topic - next topic

Another AC question

June 23, 2005, 04:24:45 AM

The clutch on my compressor will not engage (wouldn't when I bought the car). I jumped it directly to the battery with the AC controls on and it kicked in fine, so I know it isn't locked up and I'm just not getting power to the clutch. Problem is I can't find the relay (if it even has one, another long story) and don't know what else to look for. Auto-zone doesn't list a relay, I can't find anything in my Chilton's and Haynes, Advanced auto lists a relay but noone knows where it is located or how to test it.

Can anyone help me find it, or give other suggestions what the problem could be? 98 degrees consistently for about a week now and 80%+ humidity make for a long hour-and-a-half ride to work in rush hour, if you know what I mean.

Re: Another AC question

Reply #1 – June 23, 2005, 07:29:46 AM

Your low pressure switch on the dryer is what allows the compressor to kick in if there is enough pressure to do so,if not it won't.
So if there is a low or no charge in the system then it won't engauge the clutch.

Re: Another AC question

Reply #2 – June 23, 2005, 10:10:04 AM

manual or electronic climate control? there is a clutch relay inside the heater box on the ETC cars. Also there is waht is called a Wide Open Throttle relay in the system. On the 5.0 cars it is on the right front fender apr0n just behind the air filter box, also the a/c pressure switch on top of the acspoogeulator. Use a paper clip to jumper the pressure switch. If compressor kick on either the switch is bad or there is too little refrigerent in the system. If jumping that switch doesn't work try jumping the WOT relay. If that doen't work go inside the car and check. I went throught the smae thing with my air.Thats how i found the realy in the heater control bOx for the clutch signal

Re: Another AC question

Reply #3 – June 25, 2005, 12:55:44 AM

I have the manual control system. I know there isn't much pressure, if any. I will check it out Saturday afternoon. I tried once before to charge the system, but I thought the compressor had to be running in order for the 'coolant' to enter the lines. To be certain, the refill valve is located in the front pass corner near the battery, right?? This was the only fitting my pressure gauge would fit. When I tried to put the freon in, the pressure gauge read high, and it would not enter the lines, which is in part what made me think the compressor had to be engaged first.

Will I need to wire the compressor to the battery long enough to charge the lines?

I guess everyone can tell by now that this is my first time messing with the AC system...

Dave

Re: Another AC question

Reply #4 – June 25, 2005, 07:33:54 PM

I just had a similar problem about two weeks ago with my AC. My AC clutch intermitantly kicked on and off then just finally stopped engaging. I had hooked up a pressure gauge and found out I was low on refrigerant. Anyway to answer your question..yes the clutch should be engaged when charging the system. All I did was jump the low pressure switch to engage the clutch and she's good to go now. Also the connection you should be hooking up to is on the low pressure side of the system, between the compressor and the evaporator.

Re: Another AC question

Reply #5 – June 25, 2005, 11:19:22 PM

Thanks to all...I'll jump it tomorrow and try to fill again. 102 degrees this afternoon on my way to work. Not fun !!

Dave

Re: Another AC question

Reply #6 – July 09, 2005, 06:03:31 PM

On topic of this, I tried jumping my compressor earlier but it did NOT move. Red from battery terminal to red (well black with yellow stripe) on compressor and same with ground? Should kick on if it isn't seized, correct? Needless to say, the thing didn't budge. I also tried testing the wiring runinng to the a/c but the 4-pin plug confuses me. Red and one ground appear to go to a dangling plug while black/yellow and black head to the a/c. Hooked up to black/yellow and black, I'm not getting any power with the a/c switch on. Red and black give me 5v every second or so, fading off - doesn't matter if the switch is on a/c or not, it still gives those 5x spikes.

Do i have both a seized clutch AND a bad switch?

Re: Another AC question

Reply #7 – July 09, 2005, 09:21:07 PM

try using a jumper wire at the acspoogeulator switch, jump across the two wires with the a/c on and the engine running. the compressor should kick on and run. let me know what happens