A/C Comp wont turn off Corolla

[kamps989]

Hey guys I am visiting my GF in Arkansas this week as she recently moved down here and I am trying to knock out as much "handy man" work for her in this week as I can. So I recharged the AC in her 2001 Prizm today (identical to the Corolla of the same vintage) and there was not enough refrigerant for the compressor to even run before. As I was recharging the compressor began to run and cold air began to blow just as it should. The only issue is that the compressor NEVER disengages now, no matter what the A/C off on button is set etc. However it will disengage when I unhook the connector to the compressor clutch meaning to me its an electrical issue.

I have a finite time down here and extremely limited tools so any ideas would be much appreciated!

I am asking you guys this because low and behold every other auto forum for real issues seems to suck haha

 

[SFox]

Make sure the power wires aren't shorting out? How is the rest of the instrument cluster doing?

 

[kamps989]

wires appear to be in good condition and I do not see an obvious short, no meter on hand to check signals.

I know that its been a loooong time since this compressor has ran. The AC hasn't worked in years and the car has 350,000 miles on it so god only knows how long its actually been since it ran.

 

[SFox]

Alrighty. Just curious, saw Prizm and leapt on it, my GM electronic head unit is screwy enough to do that too. Had to wire in a toggle switch. All I could through google find was this: http://wiki.answers.com/Q/Why_does_..._the_AC_button_is_pressed_but_the_AC_stays_on.

I figure you'd check the simple stuff already, but maybe ... ?

 

[kamps989]

I should also mention that the fan speed only operates on high. I believe this is the resistor and don't know if one problem pertains to the other? I don't think so but electrical gremlins are not my strong suit.

 

[kimcrwbr1]

Not sure if it applies but look for the relay that controls the compressor maybe it is stuck on turn the AC off and then tap on the relay with a screwdriver handle. Pull the relay out and if it shuts off maybe the horn relay is the same put it in and if it works properly get a new relay.

 

[kimcrwbr1]

http://www.autozone.com/autozone/pa...la/_/N-jevkhZ91t25?itemIdentifier=901587_0_0_
Here is what the relay looks like

 

[snake]

I'm sure you've already checked, but make sure the temp control isn't set to defrost, it will come on by default even if the compressor switch is off on defrost. And the fan speed thing may be a clue, usually the compressor won't come on at all when that resistor goes out, even if the fan is running.

 

[adsm08]

The cycling switch could also be stuck. If the computer thinks that the pressure it always low it may never shut the compressor down.

Air conditioning is one of the few things I regularly tell people to just have a professional look at because so many things can go wrong, many need a scan tool to diagnose correctly, and many more require very specialized (reads "expensive") equipment to fix, and if not done correctly AC repairs can become very very expensive (more so than if you'd just had a pro do it right the first time) and can also be dangerous.

 

[BRUTUS_T_HOG]

It never turns off as in a/c button is off and NOT on defrost? Is this an orifice tube system or TXV system?

 

[kamps989]

Not sure if it applies but look for the relay that controls the compressor maybe it is stuck on turn the AC off and then tap on the relay with a screwdriver handle. Pull the relay out and if it shuts off maybe the horn relay is the same put it in and if it works properly get a new relay.

Well it definitely doesn't run when I pull the relay, and good call on the horn relay being the same but even with that in there it instantly turns on.

Haha no it is not on defrost

Snake:
Perhaps the resistor being out is in fact the cause then?

adsm:
I will look into what I can on that switch, I agree about having a professional look at it, but in my experience a recharge has done wonders. I know she wont wanna foot the bill on servicing it since a new car is on her to do list, if worst comes to worst I will just pull a relay so it doesn't work before I leave or leave the clutch disconnected.

Brutus:
I am not sure the type of system it is but yes it is always on with the button off and the selector on a non defrost setting.

Thanks for the ideas guys your advice as always is much appreciated!

 

[kimcrwbr1]

Allways fix the obvious first get the blower working correct. Does the heater work when you have the hvac switch to heat?

 

[black_demon69]

my bet would be climate controls in the car (fan switch and such) just a guess of course

 

[snake]

Always fix what you know is wrong first. I'd get the fan fixed and see if it fixes the main issue.