Corolla compressor clutch won't engage after charging

PatrickGSR94 on Thu July 21, 2011 1:07 AM

Year: 1996
Make: Toyota
Model: Corolla
Engine Size: 1.8L
Refrigerant Type: R134a
Ambient Temp: 85
Pressure Low: 55
Pressure High: 225
Country of Origin: United States

Got the Corolla A/C system all charged up using 2 cans of R134a. I let the first can go in, started the car, A/C switch on and fan on high, but I had to get jump the compressor clutch to get it going and pull the freon in. I figured as much since it was low. So I did that until the 1st can emptied, then just left the jumper wire on and installed the 2nd can of freon until empty. This whole time the radiator fan kept cutting on and off (engine and coolant were hot) but the A/C fan never came on. I shut off the car, removed the jumper wire, and connected the compressor wire to the harness and started the car again. No compressor clutch turning, no A/C fan.

After the 2nd can of freon, with the jumper wire still on, before I shut the car off I could feel the cold air coming through the vents. Not sure why the compressor isn't kicking on. The inner workings of the old compressor clutch gave out a couple of weeks ago, system was working fine and blowing cold immediately up until that happened, so I don't see how there could be any electrical issues.

Thoughts?

mk378 on Thu July 21, 2011 6:37 AM

Check the fuse of course, when a clutch burns up it can short the coil and blow the fuse. If it's wired like a Honda the condenser fan is on the same fuse which is in the box near the battery.

PatrickGSR94 on Thu July 21, 2011 8:27 AM

Quote
Originally posted by: mk378
Check the fuse of course, when a clutch burns up it can short the coil and blow the fuse. If it's wired like a Honda the condenser fan is on the same fuse which is in the box near the battery.

hm can't find any sign of the fuse that the compressor clutch and condenser fan are on in either the owner's manual or Haynes. I had to look at a factory wiring diagram to figure out where the fuse is. In the diagram it looks like there's an A/C fuse at the upper left, which if blown, would not allow either the compressor clutch relay and clutch (middle) or Condenser Fan Relay No. 3 (lower right) to activate. Does that look right? Unfortunately I'll have to remove the glove box later this evening to get access to that fuse. Ridiculous place to put fuses IMHO with no easy access.

Crossing fingers that it's just this fuse.

Edited: Thu July 21, 2011 at 8:27 AM by PatrickGSR94

PatrickGSR94 on Thu July 21, 2011 1:55 PM

Something I forgot to mention, when the car is running and I press the AC switch, there is no light on the switch at all. So no AC light, no compressor clutch, and no condenser fan (radiator fan works with ECT sensor, etc.).

mk378 on Thu July 21, 2011 3:07 PM

The diagram shows that the LED on the button is also powered through the same fuse. You have to find that fuse.

You're lucky that the radiator fan has it's own circuit including a pressure switch. If the fan hadn't come on when you jumped the compressor, the relief valve or a hose would have blown from overpressure. Jumping compressors with the engine running is a bad idea, on most cars the fans will not start.

Edited: Thu July 21, 2011 at 3:10 PM by mk378

PatrickGSR94 on Thu July 21, 2011 4:50 PM

Well, what are you supposed to do when charging the system in order to get the compressor going to circulate that first can of refrigerant? If the pressure switch is there to cut off the compressor clutch when there is low pressure in the system, but you only just start putting refrigerant in and need to get it circulated around, what do you do other than jumping the clutch solenoid?

I suppose if the fuse was good the clutch may have indeed started after charging with that first can (I couldn't even get all of it to go in until I got the compressor going). But many internet sources I read all said that jumping the compressor may be needed to get the compressor going initially due to the low pressure when you first start the charging process.

If you have any other tips I'd love to hear them for whenever I have to do this on my Integra (303K miles on all original A/C equipment and everything works fine *knock on wood*).

Edited: Thu July 21, 2011 at 4:51 PM by PatrickGSR94

bohica2xo on Thu July 21, 2011 8:59 PM

Jumper wires are great for selling parts.

Charge into vacuum, and the system will start on it's own.

You could have destroyed a compressor with a hot wire job like that.

B.

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"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

PatrickGSR94 on Thu July 21, 2011 11:45 PM

VICTORY!!!! That fuse was indeed blown, replaced it, and everything seems to be working as normal. FINALLY cool air!! Thanks to everyone who helped here on Auto AC Forum!

PatrickGSR94 on Fri July 22, 2011 1:29 AM

Well I went back out and after I got the rest of the car back together, I connected the manifold gauges again and found the pressures a touch low, so I added about half of another can of refrigerant. I think about 1/3 to 1/2 of the 1st can didn't actually make it in, so now it should have a charge of right around 24 oz.

Pressures at around 1500 rpm read right at 40 psi low side and 225 psi high side, give or take. I was having difficulty holding a steady engine speed and the pressure needles were fluctuating a bit. But do those pressures sound good?

PatrickGSR94 on Fri July 22, 2011 1:33 AM

Quote
Originally posted by: bohica2xo
Jumper wires are great for selling parts.

Charge into vacuum, and the system will start on it's own.

You could have destroyed a compressor with a hot wire job like that.

B.

Well, we all learn. I thought that was the proper procedure to get the initial refrigerant charge circulating as I read at least 3 or 4 web sources all recommending the same thing. Even the procedure right here in this very Procedures forums mentions this:

Quote
Originally posted by: TRB
Evacuate and Charging Procedure.

Open only the low side dial on youÃ¢ÂÂre a/c gauges allowing refrigerant to flow into the system. Again I stress the high side must be closed or you may cause personal injury to yourself or others! Start vehicle and turn on the a/c system with blower on the highest speed. In some cases if the compressor clutch has not engaged you may need to by pass the low pressure cut out/cycling switch. Refrigerant should be charged as a gas but in some cases it may be necessary to charge as a liquid. Be careful not to slug the compressor with liquid refrigerant! Charge system to OEM amounts and pressures if you are using the refrigerant the system was designed for. If vehicle is has been or is being converted start with about 60 percent of the original charging amount. After getting 60 percent of the original charge slowly add an ounce at a time until you reach the best possible vent temperature and pressure readings. If you do not know what your systems operating pressures are you can use the 2.2 x the ambient temperature as a guide. This should only be used as a guide as many systems will need more or less refrigerant to achieve proper cooling.

Edited: Fri July 22, 2011 at 1:35 AM by PatrickGSR94

Chick on Fri July 22, 2011 1:41 AM

Good information as long as a deep vacuum was pulled and charged into the vacuum, if you didn't charge into a vacuum, you're heading for trouble and I advise to start over....

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Chick
Email: Chick

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Freedoms just another word for nothing left to lose

PatrickGSR94 on Fri July 22, 2011 11:59 AM

heh yeah it got down to about 28.5" Hg within about 5 minutes, but I still left it on for an hour. It was showing about 29.5" when I shut off the pump. Then I let it sit for at least another hour or more while I was doing other stuff and the needle stayed rock solid at 29.5" Hg

Angle of this pic looks like it's at 30" but it's really just a touch under.

PatrickGSR94 on Fri July 22, 2011 12:13 PM

Another question: after I got everything working last night, I noticed the sight glass on the receiver looked clear. This was after the system sat for a day after initial charging on Wednesday night to around 18 oz. or so (system takes 23-26 oz.). After I put in a bit more of another can to get it up to around 24 oz. I noticed the sight glass looked completely solid white (foamy?). Is this normal right after charging like that? I forgot to check it this morning to see if it looks clear or not.

Cussboy on Fri July 22, 2011 5:50 PM

Don't worry about the sight glass on a R134a vehicle.

PatrickGSR94 on Sat July 23, 2011 11:36 PM

Well I checked the sight glass today after driving the car with A/C running. With it running the sight glass appeared foamy white. Then my wife switched off the A/C and it immediately went clear, then I saw a few more bubbles (individual bubbles, not foamy) come up and then it went clear again, which I understand is what it should do. Is that right?

Edited: Sat July 23, 2011 at 11:37 PM by PatrickGSR94

TRB on Sun July 24, 2011 12:12 AM

PS: There is a difference between a low pressure cycling switch, GM & Ford. And a low pressure cut out switch many other models. Never jump a low pressure cut off switch.

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

bohica2xo on Sun July 24, 2011 2:45 PM

You know Tim, you should probably edit the procedures where Patrick found that quote. Otherwise some kid will twist it just like Patrick did, and read it to mean that he should disable the HPCO and the condensor fans by hot wiring directly to the compressor clutch.

We both know something like that can lead to flying compressor parts, and could injure or kill someone.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

Edited: Sun July 24, 2011 at 5:24 PM by bohica2xo

PatrickGSR94 on Sun July 24, 2011 4:29 PM

What's with the sarcasm and attitude? I never said anybody was wrong, I just stated what I have read on here and several other system charging how-to's. If I had known the A/C fuse was blown I would have replaced it before charging and the 1st can of refrigerant likely would have made the compressor kick on. But I didn't know, and the compressor didn't kick on, and so I assumed I just needed to get the compressor turning to help it along as many how-to's recommend. If this is not the recommended procedure, then the Evacuate and Charging Procedure post should be edited as such.

But it doesn't really matter now, as the system is now fully charged and working great, thanks to all the help on here.

Edited: Sun July 24, 2011 at 4:30 PM by PatrickGSR94

TRB on Sun July 24, 2011 5:25 PM

No sarcasm and attitude. Just making it clear not to jump low/high pressure switches.

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