BIGIE

Hello guys, I used to have a problem with my air conditioner.It did not start at all when I press the AC button inside the car, no matter that the light of the button flashed. I went to a service to fix my AC and actually I have to be honest that now the AC cools down the car very well but what I noticed accidentally a few days ago is that the working mode of the AC compressor is quite unusual- the AC was on and I lifted the hood and noticed that the compressor starts, works for about 7 seconds, then stops and rest about 10 seconds, then starts again for 7 seconds, then stops and rests again fror 10 seconds and so on an so on...... Is this the proper way of working of the AC compressor?

BIGIE

And also, do you know if there is a separate computer for the AC or the central car computer gives all the information and proper signals that the AC needs to receive- about the pressure, temperature and so on?

7 UP Mustang

Normally if it is cycling off and on like you said in your post, then it is probably low on freon. Set it for maximum cold and the blower on high, and see if it is still cycling. Good luck.

BIGIE

Thank you for the advise, I will try it that way to see what is gonna happen and then share the result. And do you know how it should work if everything is normal? on what intervals of time it should start cycling and stop(approximately) ?

7 UP Mustang

A/C is one area that is not generally favorable for the DIY guys. It does requires special training and some rather expensive equipment to work on it. The compressor should run long enough to cool the car down, but does cycle to keep it from getting too cold and freezing up. As far as saying how long it should run that depends on a lot of factors, but it should not be cycling off and on every few seconds. You really need a set of gauges hooked up to it to give you more of an idea what is wrong.

BIGIE

And do you know if the air conditioner is controled by the CENTRAL car control module which controls most of the car or there is a separate control module for the AC itself?

7 UP Mustang

I was certified to work on the old R-12 freon systems, and have not worked on the newer models. I do know the A/C system has devices to cut off the compressor to protect it from such items as low or high pressures. I think everything on our newer Mustangs is controlled by the computer, but I am not absolutely certain. Good luck.

mstngsule68

you should still be covered under warranty, just take it in.

BIGIE

and do you think that there's a chance for me to find the electronic diagram of the AC, I mean the way the power comes to it from the computer, the wires, modules etc., you know, the "wire diagram" I think that this is called?

BIGIE

Hello again, I think that a solution of my AC problem was found, there's a guy who will connect a separate control module to control the timing of cycling on and off of the compressor but I need to know on what intervals of time approximately the compressor starts and then stops, I mean how many minutes it works and then how many minutes it rests? I know that this can not be exactly done as the factory settings but I need to know the approximate timing of cycling on and off to adjust the separate control module?