John,
  There should be a double connector near the compressor.  One wire to the
compressor is the ground for the clutch; the other is for the 12V from a
relay somewhere.  If you disconnect it and connect a ground wire and a
jumper from +12V at the alternator you should be able to hear the
compresssor clutch click if everything is quiet or make the compressor run
if the engine is running.  You can use a fuse in your +12v connection if
you want to play it safe.  Page 97.144 in my Bentley

Good luck,
Larry A.

On Tue, Sep 6, 2016 at 10:44 PM, John Rodgers <jrodgers113@gmail.com> wrote:

> I want to check that the clutch does in fact, operate. I should be able to
> put power just to the clutch to see if it engages. This should be doable
> with engine and compressor off. But I don't really know how.
>
> John
>
> On Sep 6, 2016 19:25, "Dan N" <dn92610@gmail.com> wrote:
>
> I have a '88 Carat and the AC works fine for 2 years then one day it stops
> working and work again - sort of cycling... compressor not engaging.. I
> changed the temp knob just to be sure and check all the fuses.. it worked
> for few days and then stops and works again.. intermittent symptom... one
> day check all the connectors at the rear pillar and suddenly the compressor
> engages again.. I cleaned up that connector, make it tight and it works
> good since then
>