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A/c compressor

my 2000 toyota rav4 ac compressor shuts down after running for a few minutes. does anyone have any idea what the problem is?

Does it still blow cold air? Some of them are designed to cycle on and off. Are you saying when it’s hot outside and you select cold air the compressor runs for a few minutes then shuts down and doesn’t start again and then your car fails to provide you with cold air? If that’s the case, I’d look at a bad AC clutch? You can check power to it and see if it’s still getting 12 V to the clutch plug. If so, and the clutch isn’t engaged then it’s a bad clutch. If not, it could be a relay, (it might have a resetable relay, similar like a circuit breaker in your house, but smaller, and this one resets itself after a period of time), or a bad temp sensor in the system.

Try setting it to defrost and see if it shuts down. In not, nothing is likely wrong, but if it does the same thing on defrost, likely you are low on refrigerant which means you have a leak. Best bet is an A/C shop (check with your local radiator repair if you live up north where it is cold) and have them find the leak and recharge as needed.

I would advise against the diy kits.

I second Mr. Meehan about the low refrigerant charge.
Since the vehicle is going on 9 years old that would not be unusual at all.

it blows cold air for a few minutes then the compressor clicks off and the fans that are in front that cool down the engine turn off also. i only know this because my mechanic showed me.

prior to showing me this, the mechanic had vacuumed the system out and added new refrigerant.

The computer is shutting down your AC because at least one of its sensors is telling it that something is wrong. I suspect you will have to take it somewhere that has the right test equipment to read the specific Toyota AC trouble codes to be able to figure this one out. Some of the things that it could be are wrong pressure reading on low side, wrong pressure reading on high side, over/under temperature at two or three different locations, or wrong shaft speed on the compressor. Personally, based on the history, I suspect that the shaft speed may be the issue. Maybe the speed sensor was damaged during the other work you had done? Maybe the clutch is slipping now?

Nitpicking for a moment, the proper terminology for “vacuuming” the system is “evacuation”.

So this begs the question. Why was the system evacuated? Parts replacement or simply low on refrigerant? If low on refrigerant then why did the mechanic not find out the source of the leak and repair it?
If the system was low before then why do you think it’s not low now or that the pressures in the system are even correct?

http://community.cartalk.com/posts/list/2119210.page

We need to write a seasonal “check this first” type of thing for the comming AC season. Anyone care to write it,or contribute? How about it CT,how about we post some general AC tips. I can write it along with many others,we seem to be answering the same questions every AC season.

i appreciate all your answers and thank you (although i am confused by some answers). i am a woman who understands very little about what happens under the hood of a car and i have to go by what my mechanic tells me. although i trust him to some degree, i like to have a little knowledge so that i can either 1) prepare myself mentally for a massive bill or 2) have a conversation with the mechanic with what he proposes to do and at least challenge him a little (he is the expert and not me after all) if your answers differ from his.