Hey guys, im having issues with my a/c compressor. I have a switch to power the a/c or else it draws current constantly (even when the car is off, which would drain the batterry. When i turn the switch on, it powers the a/c and obviously i get cold air, and vise versa when i switch it off... and now when i switch it on, nothing happens.

does anybody have any ideas as to what it may be? I've been told it may just be the clutch on the A/c, but idk much about it....

And all my fuses are good btw...

 

Well what exactly does the switch power?
What exactly is drawing power with the car off?

 

As pmohr is saying, it is not possible to run the a/c compressor with the car off. It is driven by the serpentine belt, which rotates with the engine. Do you mean the fan/blower on the inside of the vehicle?

 

No, it sounds like the clutch stays powered which will drain a battery. Pull the relay, does the clutch power off?

Someone had a harness problem or ran power directly to the relay for some reason rather than let the system control the A\C. Check the relay and the power to the switch and figure out if the hack was even ever needed.

 

Yes thanks, i word the a/c system very bad lol.

it's been like this for a while, i found out the hard way killing a battery, which led me to my optima red top. i've done alot of work to fix the draining issue, so i will take a new look and try to figure this one out....

updates to come...

 

well all my wires/fuses/relays are good, now its time for the voltage meter and possibly a friend who knows other things on what to do! lol anything else have a possiblity?

 

You still haven't mentioned exactly what the switch is hooked up to. Without that minor detail, we can't really be of any help.

 

Alternator buddy

 

The switch is hooked up to your alternator? That has nothing to do with the air conditioning system as you posted. If you seek help, I don't see why you would outright mislead us from the start.

Again, EXACTLY WHAT is it hooked up to? What wire, coming from and going to where?

 

well there is ONLY ONE wire the goes from the alternator to the a/c.



now, im a noob but when this wire is attached, it keeps the a/c on CONSTANTLY (even when the car is off, causing the battery to die) so i ran a toggle switch into my car so i could disconnect this from my seat. This stopped my battery from dying when the car is off...now when i try to use the a/c it no longer kicks in.

sorry, look at image sideways

 

There is no wire going directly 'to the AC' (assuming you mean the clutch on the compressor? You still have neglected to mention specifics) from the alternator.

How is the 'ac on' with the engine off? As has been said, the compressor is belt driven; it can not engage with the engine off.

Is that the B/P wire going to the compressor clutch? That doesn't go to the alternator, it goes through the fusebox to B+.

Have you not checked the fuse for the compressor clutch? Again, if you pull the relay, does it not keep the battery from discharging? You ignored that question.

If that compressor clutch wire stays energized at all times, then you've got a shorted relay, a short to ground between the ECU and the relay, or an ECU problem.

 

that sucks.

 

thanks for the possible problems...that was all i was asking for...

like i mentioned before...i am not good with wording the a/c system, please bear with me. But yes you basically explained what i was trying to say. excuse me for being the retard here.

 

Hey guys, I have a similar problem here. My a/c compressor was not turning on. I changed all the relays and got nothing. I then tested the relay output with a test light and out of 4 I only got 1 positive and 1 negative. The other 2 did not give me a light for - or +. I then took a wire from the - on the battery and tried it on the 2 blanks and on the negative output. Nothing. I then switched the wire to the positive on the battery and tried the same with the same results. For some reason I decided to put the positive wire on to the - output on the relay and the compressor turned right on. Also, before all of this my fans only worked when wired directly. Once the compressor started working it fixed my fan problem. I left it over night and it drained my battery. I am a noob, especially when it comes to electricity. Does anyone out there know something that I dont? Any help would be greatly appreciated. Let me know if you need any more details.

 

well anytime you run a 'hot' wire to anything especially bypassing a circut such as a relay you will be drawing constant power from the battery. it's the same as leaving the dome light on, eventually it will drain the battery. I'ld say fix it right but if ya don't wanna fool with it you can run a toggle switch to the dash so you can easily turn it on/off. just don't forget about it or you'll be stuck out once again. use a lighted switch if you choose that route so it will catch your eye.

 

If the system charge is low (R134) then your compressor will not run.
Have you verified the system has the correct charge, if any at all?

 

holy 3 year thread bump, Batman!

 

Yeah - but he has a legit problem and he searched. It's not like he's saying "Me too".

 

True enough

 

yeah if it's low on freon the compressor won't kick on unless you run a 'jump wire' to it. that is a safety feature to keep your compressor from burning up due to lack of proper operating conditions. like I said fix it right for a lil now or spend alot later replacing all the a/c components. I bought a used compressor from the junkyard and replaced mine when it went out. did everything myself. either take it to a shop and pay 75 bucks if it's just a simple recharge job or you can do it in your driveway with the cheap kit from the parts store. if you don't already have the stuff you'll spend almost as much as if you took it to the shop, just use someone you can trust so they don't rip you off.

a question that I don't remember seeing answered is how does it work when the compressor is manually turned on? does it blow cold, cool or hot? that bit of info will be really helpful in figuring out what is wrong.

 

At first I thought this was the problem. I put almost 3 cans of R134 and the compressor still was not turning on. Once I put the HOT wire to the relay the compressor turned right on. I took it to an A/C shop to check the pressure on it and they said that the pressure goes up and down. He said that the compressor might be ready to give up but it will still run. As for my problem he simply said that it was an electrical problem.

@ADROX
With the compressor manually turned on, it will blow freezing cold air on all levels of the controller. But when I turn off the switch, the compressor stays on. I ran a toggle switch to turn it on and off for now, but like you said, I want to fix it right. Also, when the compressor is not on the fans will not turn on. With it on manually the fans work as they should. My problem is electrical and I am stumped at the fact that the compressor only works with a HOT (+ wire) connected to a negative output on the relay.

 

not sure exactly how what I am about to say works... but don't the fans run per a/c? in particular the fan speed or both fans working at once?
maybe a fan switch or relay is the problem. I would definately try to eliminate all causes of the compressor not working properly first. I can never really understand them but a wiring diagram would be helpful in both phases of this. might be an extra relay there somewhere that you just don't know about.
I'ld say if the air is cold the compressor is fine but then again the problem I had was the compressor would just work when it wanted to even after I had it recharged at a trustworthy shop. check the connections real good to on the compressor and clean as best you can. they can get pretty nasty if there's an oil nearby.
I'll check into a bit more when I get back in this evening for you.

 

@ ADROX
Here's an update.... I'm ruling out the relay because I swapped out all of them with my wifes' 96, which has no problems what so ever. I also swapped the TEMP Sensor (I don't know why but I said screw it why not). She still has no problems with her A/C and my compressor still didn't turn on. I am going to try to swap the A/C controller from her car to mine when she gets back today to see if that will help. If that doesn't work I'm afraid the ECM might be the problem or some really F'd up wiring. I did some more research and found the troubleshoot on the Manual. I don't know how to post it here or if I am even allowed to post it here. Its in section "HA" pages 53-55.

 

oh yeah, have you checked the pressure switch??? believe its on top of the drier. you can use a jumper wire to check and see if the compressor will kick on when you bypass the switch.
if everything works when you jump it that's probably the problem. I'ld say check the good one on the other car to it before you buy one though. I personally hate electrical work it's a real PITA. might just be the compressor this whole time but wouldn't think so. electrical issues suck.