huesero

I have a 1997 300 ES with 125K mi. This is a problem thats been going on for a while now and getting progressively worse. Now that summer is coming, Im finally going have to get it fixed. I thought I would pick the brains of the expert enthusiasts before I lay down some coin.

When the car is idling or relatively cold, and running level, the A/C works with the green light on the button.
When the car heats-up, or runs on a grade, the light on the button goes out, and so does the A/C.
If you push the button twice, the green light goes on, and so does the A/C, for a while, and it cycles all over again.
You can hear and feel the compressor cycling on and off with this maneuver.
When it first started happening, the time lasted longer. Now it seems that the cold air is only on for a few minutes before it happens.

I searched the threads and posts and these are some of the responses I've seen:
1) Replace A/C filter
2) Refrigerant deficiency
3) Magnetic clutch relay dysfunction
4) Compressor malfunction

I opened my A/C filter housing only to discover there was no filter in there.
While putting one in will help my lungs, somehow, I doubt putting one in will solve this problem.

Charging the system seems easy enough, but its not an issue of being cold enough, as it seems to be cool when it actually works.

What and where is the magnetic clutch relay?
Is it costly? Can you replace it yourself?
Is there anyway to differentiate this switching mechanism from the actual compressor?

Replacing a compressor sounds the most expensive. What is a reasonable cost to install? I imagine this would also require re-charging the system.

Finally, I seem to remember seeing someone being able to display diagnostic codes on their radio by pushing a combination of buttons during start-up on an LS model. Is this possible with my ES?

Any tips are much appreciated.

tuan92129

I would try the repairs in that order. Same problem in my parents es300 (2003) and solved with a new Cabin Filter.