i trying to trouble shoot the a/c on a 1996 ford taurus. the compressor doesnt kick on. i have checked the fuses, both inside the cab and engine compartment, and have found none that are bad. i have also tried jumping the low pressure, and high pressure switches. the system itself shows full. i thinking maybe the relay but i cant seem to locate it? any body know are have a pic of where it is? or have other ideas what it could be. thank you.
Checking The A/c To See Why I Doesnt Work
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If you jumper the low pressure switch (AC on, engine running) the compressor should kick on. You should not have to touch the high pressure switch. This is just a test, only do it long enough to determine the compressor works.
Did you hear anything when you jumpered the low pressure switch? You jumpered the connector, not the actual switch, right?
How did you get your "full" reading? Was it one of those gauges that attach to the low side? Those are horrible innacurate and always read overfilled or full when the system is off. They are ONLY to be used as a general refrence and only when the ac is on. The low side pressure drops dramatically when the ac is on, so checking it is useless when the compressor is stopped.
Did you hear anything when you jumpered the low pressure switch? You jumpered the connector, not the actual switch, right?
How did you get your "full" reading? Was it one of those gauges that attach to the low side? Those are horrible innacurate and always read overfilled or full when the system is off. They are ONLY to be used as a general refrence and only when the ac is on. The low side pressure drops dramatically when the ac is on, so checking it is useless when the compressor is stopped.
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Next thing I'd do then is test for power at the compressor. There is one main wire running across the compressor that goes into the clutch coil. Test to see if this wire is getting 12v, if so the clutch coil is bad (seen bad pulley bearings do this). Even if it's not you can still give it power and the compressor will turn on. If it's not getting any power then hmm, that's past my experience, haha.
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I just replied to your OBD II thread and then I came across this thread too. Too coincidental not to at least look closer.
I think I know what your problem is.
Go here -
http://www.v8sho.com/SHO/Engine%20Harness%...20Emissions.htm
Scroll down to the wire plug and pinout info. I think you have the same mismatched wire loom issue that I had.
I think I know what your problem is.
Go here -
http://www.v8sho.com/SHO/Engine%20Harness%...20Emissions.htm
Scroll down to the wire plug and pinout info. I think you have the same mismatched wire loom issue that I had.
QUOTE (Zenriddles @ Apr 21 2009, 12:43 PM) index.php?act=findpost&pid=719342
ok i will check that out. do you happen to have any pics, so i can make sure what im lookng for?
i changed the wiring on the plug. those two wires were different. so i switched them. but still no a/c. i tried jumping the low pressure switch again, and the compressor clutch still never kicked in. now i havent been able to test the clutch for power as i havent figured out how to get to it? it is so tight i cant get in there and unplug the a/c clutch connector to test, any ideas or tricks to that?
Does your car have closer or over 100K miles? Have you ever replace the ac clutch pulley or bearing?
When the ac clutch pulley bearing goes bad (you might get 100K miles before it dies), if you don't replace the ac clutch pulley immediately, the pulley will wobble whenever the engine is running, and it will make contact with the ac clutch coil ruining (damaging the windings) shorting it out.
At that point you will need to replace the ac clutch set (magnetic plate, ac clutch pulley, and ac clutch coil) or the complete ac compressor with clutch set.
You can check the ac clutch pulley bearing with the compressor in the car by removing the serpentine belt, giving the pulley a spin, and observing what happens. If it grinding, or is loose, or spins freely, or spins canted, or wobbles, then the bearing is bad, and you need a new clutch pulley. If you can see or feel it hitting something, then you waited too long, and the ac clutch coil is ruined as well.
If the pulley spins true, and smooth with a little drag (that should be the grease inside of bearing), then the clutch pulley should be okay.
The flat plate on front of the ac clutch pulley is the magentic plate. It moves in and out when the ac clutch coil is energizes to engage the ac compressor. If the gap/clearance between back of the magnetic plate and the front of the ac clutch pulley is/becomes too large, then when the ac clutch coil is energized, the magnetic plate may not move to engage the ac compressor.
There is a spec for the magnetic plate clearance. If I remember correctly it is between .015" and .030". Some people have suggested using a broomstick while the engine is running with the ac switched on to push the magnetic plate towards the ac pulley to see if you can force the magnetic plate to engage the ac clutch pulley. This may prove that everything is working, but that the magnetic plate clearance needs to be reset.
You need to buy an ac manifold gauge set if you are serious about working on your ac system. The little gauges that come on refrigerant cans is a joke.
When the ac clutch pulley bearing goes bad (you might get 100K miles before it dies), if you don't replace the ac clutch pulley immediately, the pulley will wobble whenever the engine is running, and it will make contact with the ac clutch coil ruining (damaging the windings) shorting it out.
At that point you will need to replace the ac clutch set (magnetic plate, ac clutch pulley, and ac clutch coil) or the complete ac compressor with clutch set.
You can check the ac clutch pulley bearing with the compressor in the car by removing the serpentine belt, giving the pulley a spin, and observing what happens. If it grinding, or is loose, or spins freely, or spins canted, or wobbles, then the bearing is bad, and you need a new clutch pulley. If you can see or feel it hitting something, then you waited too long, and the ac clutch coil is ruined as well.
If the pulley spins true, and smooth with a little drag (that should be the grease inside of bearing), then the clutch pulley should be okay.
The flat plate on front of the ac clutch pulley is the magentic plate. It moves in and out when the ac clutch coil is energizes to engage the ac compressor. If the gap/clearance between back of the magnetic plate and the front of the ac clutch pulley is/becomes too large, then when the ac clutch coil is energized, the magnetic plate may not move to engage the ac compressor.
There is a spec for the magnetic plate clearance. If I remember correctly it is between .015" and .030". Some people have suggested using a broomstick while the engine is running with the ac switched on to push the magnetic plate towards the ac pulley to see if you can force the magnetic plate to engage the ac clutch pulley. This may prove that everything is working, but that the magnetic plate clearance needs to be reset.
You need to buy an ac manifold gauge set if you are serious about working on your ac system. The little gauges that come on refrigerant cans is a joke.
i works fine now. i went to check the power going to the compressor and pulled on the wire and i works great now. i started working after i switched the 5 and 10 wires on the c130 plug. and after testing the power wires to the compressor.
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