air conditioner compressor clutch won't engage

Hi there,

it sound as if the pressure switch has cut in, so i would go get the system pressures tested as this will give your tech a good idea as to what is going on.

Mark (mhpautos)

Hi- thanks for your fast reply- my tech ( without much toyota experience) checked charge while the compressor was jumped to engage. It was cooling well and the freon was charged. It will raise idle and react to A/C button, but won't engage A/C clutch. No fuses appear blown.
thanks

Hi there,

He will need to check that the pressure switch has not activated, bridge out the switch and see if that turns on the system, if so a pressure or switch problem, if not a power supply issue to the compressor, check this next.

Mark (mhpautos)

I have a 2003 Toyota corolla LE.the Clutch on the compressor was not engaging, so I checked to see if there was power going to the compressor unit, and there was not. I went to advanced auto, they checked for power at the compressor also and it had power then. They advised that I need a compressor unit. I purchased the new unit,installed it, and now three's no power again at the compressor now. I checked the fuse and it is good. I ran a power jumper wire from the positive battery terminal to the hot wire leading to the compressor and the clutch will come on and gets fairly cold , and stops when the jumper wire is disconnected. please help me on this issue. thank you ,in advance, for your valuble time pertaining to this matter.

The most common issue when this happens is the AC cycle switch. It is what determines when power is sent. Check that first.

Thank you Jacob and Nickolas

Let me know what you find.

Joe

Hello, Im trying to find the location of the low pressure switch for a 98 corolla. I followed the low pressure line but cannot locate the accumulator (canister shape) where the low pressure switch is said to be located. I rather use this method then jump the compressor from the battery. Any help would be greatly appreciated.

Low pressure fitting is on low pressure line between evaporator and compresor.

[quote:d6a295ddd3="mmprince4000"]Low pressure fitting is on low pressure line between evaporator and compresor.[/quote:d6a295ddd3]

Hello, Thanks for the reply. I actually know where the low pressure line exists and where the freon goes. But the problem is when I put a gauge to the low side it read around 38 psi which led me to believe there was freon already in the system and it hadnt leaked out. My compressor doesnt turn on when the AC is on so I wanted to try to start it by jumping the low pressure switch but I cannot seem to find that.. I just want to confirm its not the compressor causing my ac not to work. Thanks for all the help

Disconnect electrical connector at compressor and hook up DVOM to harness connector, turn AC on and measure voltage, if none, then switch, if voltage is present then compressor clutch/compressor would be suspect.

I am on disability and not in great shape physically, but my mind still works It just takes longer to do things, I am a retired field service engineer..
I bought this car used and after a week out so the A/C stopped blowing cool.
I checked the fuses with a meter and none were bad. The compressor did not click on when the controls were set to max A/C. and the button for "AC" depressed. The cheap gauge i have showed the Freon pressure in the green "good" zone..
So I ran a jumper to the compressor and it does click on and engage when jumped, but the A/C still blows warm.
I have had some problems with the dome light, cigarette plug, radio, but do not know if they coincided with the A/C issue as I bought it in October and was not using the A/C but know it did work when I bought it.
Are there any common problems that may save me some time to check first? I currently have the dash apart and the A/C button appears to be activated by two different means. I have not taken it apart or tested it properly yet as it is so dang hot, and I really have no place to work on the car.
Help!

Hello,

If the system has Freon and the the system will not get cold, jumped are not then the compressor could be bad, the only way to tell for sure is to connect a gauge set tot he high and low side to get the readings, here is a guide that will help you see whats going on.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

and

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

and

https://www.2carpros.com/articles/replace-air-conditioner-compressor

Please run some tests and get back to us so we can continue helping you.

Cheers, Ken

I have a 1998 chevy prizm. The a/c stopped working. I have discovered that there is no voltage going through the contacts of the A/C MG relay. That is the voltage to the mag clutch. There is voltage on the coil side just no completed path. How often do A/C amplifiers go out or is there something that has to be met to tell the amplifier to complete the circuit? in otherwords there is no ground.

Thermostat control, thermistor, ECU and AC pressure switch are some of the items telling the amplifier to earth the mag clutch relay primary coil.

On my 1993 toyota corolla (1.8 liter - 120,000 miles) the ac compressor clutch burned and I replace the compressor with a new switch. I vacuum the system and filled with freon. I turn the switch on and the compressor will not come on. I applied 12 volts at the compressor clutch and it came on. I tried at the switch again and even bought a new switch and the compressor still does not come on. I checked fuses and still the compressor did not come on. Is it possible I missed a fused, or fusible link that is hidden are in an unseen location? Please help me!!!
I would also like to know if a metal timing chain can be put on the corolla instead of a belt.

The compressor requires a correct refrigerant charge providing power to the A/C relay it must be energized and provides power to the compressor. There is also an A/C amplifier in the circuit. Good luck

my aircon run in a few minutes and then the compressor clutch release then after a few minutes it will engage again and vise versa.i've check the pressure of the gas and it comes to 45 while runnig but when the compressor clutch release the pressure goes to 100.what is the cause if this problem and why is it that the pressure of the gas got high, what was the cause of this?

Hi sonny_0904,

You seems to have too much freon in the system.

When compressor is operating, pressure should be about 30 psi and when compressor stops, the static pressure should be about 90 psi.