Toyota sienna - a/c light blinking

I have a 2007 toyota sienna where the a/c light flashes 42,000 miles and will not blow cold air consistently? When the engine is idling and we turn on the a/c the engine will cutoff. we took it to the dealer and they are saying that the compressor is bad on it and should be replaced with a 3000 pricetag. I read some of the other posts and they hint that it could be the magnetic clutch relay, could this cause all of the above symptons?