'89 Camry A/C Compressor Not Running

[89DLXV6]

Hey all,

As the title states I have a 1989 Camry DLX V6, and the A/C Compressor is not turning on. I've only had the car for 2 months, and have only recently needed the A/C. When I hit the button to turn it on, the compressor is not kicking on at all. Clutch doesn't engange, no drop in idle speed, nada. The green light on the A/C switch -does- come on, and stays on.

All though I can fix just about anything on a car, this is the first time I've encountered a dead A/C. Before I drop $300 on a new compressor, is there anything else that may be faulty that would cause the compressor not to kick on? I've read that if there is too low of a refrigerant charge, that may cause it not to come on at all; But am not sure on the validity of that remark.

I've done many searches on this forum, and the newsgroups and have only come up with posts pertaining to a dead Expansion Valve. Nothing about a compressor not coming on at all. Are there any test procedures I can go through to narrow this down, or does it sound like I just need to replace the compressor?

My worst fear is that the previous owner tried to retrofit the system without vaccuming out the R12 and mineral oil, thus frying the compressor. Only problem is, I'm not sure if it has been converted to R134a at all, or how to go about checking as the only difference externally is the Hi/Low adapters, and I'm not sure what I'm looking for to know the difference there.

Thanks for any assistance.

Regards,
Matt

[PoR2GeEzCamry]

my 89 camry has the same problem. I hit the ac button, light turns on, but nothing happesns with the compressor. What is the fix for this? New compressor?

[chronoti]

yes there a thing call the low pressure switch it wount allow the compressor to turn on also it will turn the compressor off if the pressure is too high. also there a temp sensor on the evap that can turn off the compressor when the coils get too cold. the clutch on the compressor could be bad.

as for the gas dont trust it, pull the system and clean out the old oil and o-ring, also the dryer. dont chance it we have 2 cars converted to R-134a and we havnt change the fittings for the new gas.

chances are that the clutch or temp sensor is bad, you can try getting a new temp sensor from a junk yard (prolly a dollar if you poket it) and check resistance for the thing that engauges the clutch make sure it's not grounded out or open.

[89DLXV6]

Originally Posted by chronoti

yes there a thing call the low pressure switch it wount allow the compressor to turn on also it will turn the compressor off if the pressure is too high. also there a temp sensor on the evap that can turn off the compressor when the coils get too cold. the clutch on the compressor could be bad.

as for the gas dont trust it, pull the system and clean out the old oil and o-ring, also the dryer. dont chance it we have 2 cars converted to R-134a and we havnt change the fittings for the new gas.

chances are that the clutch or temp sensor is bad, you can try getting a new temp sensor from a junk yard (prolly a dollar if you poket it) and check resistance for the thing that engauges the clutch make sure it's not grounded out or open.

Would the low pressure switch also be known as a 'Dual-Pressure Switch' or 'Binary / Trinary Switch'? i.e, this - http://www.partsamerica.com/ProductD...pe=893&ptset=A

I wouldn't think the coils are getting too cold, as it's not turning on at all. But I can see where you are going with that as if the switch is bad it may just be tricking the compressor into thinking it's too cold all of the time, and preventing it from turning on.

I was suspecting the clutch could be bad too, but wasn't sure if the compressor would still make some sort of noise while trying to engage the clutch - at this time the compressor makes no noise.

I saw the post somewhere about what that resistance should be. I believe is is supposed to be between 2 and 4 ohms, is that correct? I think I saw two different wiring leads on the compressor when I looked. I'm assuming I need to check the one closest to the clutch, on the very top of the compressor. Is this correct? If so, should I check clutch side of that connection, or compressor side? If it is grounded out or open, would that indicate a faulty clutch, or compressor?

Thanks for the quick response and good ideas, very much appreciated in this 95 deg+ heat.

Regards - Matt

[weaktruk]

Originally Posted by chronoti

yes there a thing call the low pressure switch it wount allow the compressor to turn on also it will turn the compressor off if the pressure is too high. also there a temp sensor on the evap that can turn off the compressor when the coils get too cold. the clutch on the compressor could be bad.

as for the gas dont trust it, pull the system and clean out the old oil and o-ring, also the dryer. dont chance it we have 2 cars converted to R-134a and we havnt change the fittings for the new gas.

chances are that the clutch or temp sensor is bad, you can try getting a new temp sensor from a junk yard (prolly a dollar if you poket it) and check resistance for the thing that engauges the clutch make sure it's not grounded out or open.

Man, this guy knows what he is talking about! It would be wise to listen to him

[chronoti]

yes that switch would be it. i dont have a repare manual for the gen 2 so i cant tell you exatcly what it's spota be at to check those things and i dont want to tell you anything wrong

[89DLXV6]

Originally Posted by chronoti

yes that switch would be it. i dont have a repare manual for the gen 2 so i cant tell you exatcly what it's spota be at to check those things and i dont want to tell you anything wrong

Right on, I'm going to replace both of the compressor cut-off switches (speed sensor and dual-pressue) As well as the drier and expansion valve. That is regardless if they are bad, as I know the drier needs to be replaced when you retrofit either way and they are all fairly cheap parts new. I found that information on the clutch coil resistance, posting it for future searchers:

"Hook black lead of meter to ground and with clutch unplugged
probe wire going into clutch coil with red meter lead,you should get a reading
of under 3 ohms.anything higher than 5 ohms is too much and would indicate a
faulty coil."

Does that sound about right?

I'm also going to have the system vacuumed AND then I'll remove the Evap core and flush it, as well as checking the core temp sensor, prior to refilling with R134a. I don't want to risk any oil cross contamination so I'll just do it right the first time.

I'm going to pop the belt on Thursday when I have off and try to spin the compressor, hopefully it's not seized. If so, I'll get a new compressor as well.

-Matt

Edit: One more question. Is the clutch coil built into the clutch, part of the compressor, or standalone? I found that you can buy just a clutch coil from Toyota, but it is about the same price as an aftermarket clutch.

[pschultz]

I assume you have tried jumping from the battery to the compressor? If the freon level is too low the compressor will not come on (that was my problem after changing over to R134a). Also, (and my current problem), if the idle speed is too low, the compressor will kick off. I sometimes have to put car in neutral and race engine at a traffic light on a hot day. I have heard this is due to a bad ISV (idle speed valve) but I do not know how to replace it.