"AC doesnt work"
Thread Starter
Drifting
Joined: Aug 2001
Posts: 1,823
Likes: 1
From: Arlington TN
"AC doesnt work"
One of the cars I'm looking at.....AC doesnt work, but all parts look to be there.
Anyone got some good Troubleshooting checklists on what it could be?
i.e. - I know that I could try to turn it on and I hear it cycling, the compressor *might* be good....or it *might not*. If turn it on and nothing happens, maybe a bad switch, etc etc.....
Any simple 20 minute set of checks that could make me say....ok 500 dollar repair vs STAY AWAY!!! TOO MUCH TROUBLE?
Thanks!
Anyone got some good Troubleshooting checklists on what it could be?
i.e. - I know that I could try to turn it on and I hear it cycling, the compressor *might* be good....or it *might not*. If turn it on and nothing happens, maybe a bad switch, etc etc.....
Any simple 20 minute set of checks that could make me say....ok 500 dollar repair vs STAY AWAY!!! TOO MUCH TROUBLE?
Thanks!
Pro
Joined: Oct 2005
Posts: 581
Likes: 0
From: Boynton Beach Florida
a/c
see if you have 12 volts going to the a/c low pressure switch.if you don't check the plug in back of the a/c control on the console.then you have to have 12 volts comming out of the pressure switch going to the a/c clutch ,if you have the 12 volts and it still don't work check the ground. also if you don't have 12 volts comming from the pressure switch its low on freon..if you jump the pressure sw. it might work but don't let it run low on freon.
Thread Starter
Drifting
Joined: Aug 2001
Posts: 1,823
Likes: 1
From: Arlington TN
Originally Posted by Easy Mike
Define "doesn't work." Does it not come on (no power); does it come on but doesn't run cool? Does it run cool but not cold?
Thanks for the gouge to everyone.
Instructor
Joined: Sep 2004
Posts: 193
Likes: 0
With the engine off, see if you can physically turn the clutch on the inside of the A/C compressor pully. If you can't even budge it then the chances are the clutch is frozen - you might try some WD-40 to free it and if that doesn't work it is toast. You might be able to replace the clutch, not sure. So, it turns, then what? Look for the low refrigerant switch (black round) on the aluminum cylinder on the (probably) passenger side inside the fender well. Un plug the plug. Start the engine and use a jumper to jump the two blades inside the plug wire. Don't hold them for a long time, just a second or so. If you hear the compressor kick on then you either have a low refrigerant situation or you need a new pressure/coolant detection switch. If you haven't run it in awhile and it used to work then the chances are you are low or out of refrigerant (freon). You can always replace the switch to be sure. After that it is on to the a/c shop to have someone evacuate the system and test for leaks. If you have to go that route I would have them convert it to R134 since R12 isn't being made anymore thanks to Uncle Sam and what is out there is getting really expensive. Good Luck.
