2000 v70 AC Goes Warm after long idle

redsouther · Post by **redsouther** » 06 Sep 2006, 12:59

I just bought a 2000 v70 with approx 94k miles. It's in great shape, and I can find very little wrong with it. However, I've noticed that if the car is allowed to idle for more than about 5 minutes with the air conditioning running, the air becomes warm when you begin to drive again - as if the compressor has stopped. After driving for a while (or after shutting the car off and restarting) you can hear the compressor start again, and the air is cool.

I read that there is a superheat switch on the compressor that, if set too low, can cause the compressor to shut off like this. I also read that this switch can be bypassed, but is this safe? Has anyone else experienced this problem? Thanks.

cn2000 · Post by **cn2000** » 06 Sep 2006, 13:25

Probably the clutch coil. No overheat sensor on these, it seems. Mine also has some kind of short in it when it runs awhile. Yours could have something else wrong with it, but see my post below a few posts: "V70 compressor quits..have to wait" (Also, check your battery cable to the relay compartment, make sure its not cooked for lots of reasons including a/c)

cn2000 · Post by **cn2000** » 06 Sep 2006, 13:34

You should verify the functionality of the rest of the system first though,

run with Guages on it,
check high and low pressure switch continuity...ect

The quick and dirty:
-check for power to the compressor when it cylces out with a DVOM.
If you have power but no engagement your clutch/coil is bad, provided the wire that runs from the relay to the compressor ohms out good. (Purple wire)