when i push the ac button nothing happens. how can i tell if the compressor is good or not because it is not turning on.

One exactly does "nothing happens" mean? You have checked that the compressor is not turning when you do this? Is the A/C fuse in place and good? Is the compressor connectors connected? With the engine off, can you turn the compressor by hand?

what he said. Usually does nothing means no freon, but check the fuses.

 

nipper

the fuse is good, i can turn it, it's plugged in.

open the hood and check to see if the compressor is turning and that the belt is running

the compressor is not turning.

most likley there is no pressure in the system.

 

nipper

... Usually does nothing means no freon...

What he said. Have someone turn on the A/C while you watch the compressor; does it turn for a moment then stop? There are pressure and temperature sensors, typically mounted on the receiver/dryer. The most likely is that the pressure sensor is giving a no-go for the compressor clutch. You can try bypassing the sensors for a moment and see if the clutch engages (or you can directly activate the clutch.

The problem may also be due to a faulty relay for the compressor.

how do i test the compressor, what wires do i use. is it the 3 wire plug on top of the compressor.

how technical are you, its easier to check a pressure switch firts, do you have a meter?

 

nipper

how likely is it for an ac relay (in box under hood) to go bad?? and do you just check with a meter?

 

 

NOTE... i havent gotten my ac fixed yet..

how likely is it for an ac relay (in box under hood) to go bad?? and do you just check with a meter?

 

 

NOTE... i havent gotten my ac fixed yet..

 

Bad relays are a pretty common failure item since they carry a good amount of current that can be hard on the contacts.

 

You can also use a test light probe to see where voltage is getting to and where it isn't.

how do i check the pressure switch, and the relay.

Just measure the voltage across the leads. When the contacts are "open" you will see voltage drop across them. When the contacts are "closed" there should be no voltage across them (a short).

 

With a relay you will have more than two wires. The swtiched contacts are usually the two larger leads that have to handle the current load. If you can find another relay that matches the suspected bad one just swap them.

voltage readings can give a false reading, i was going to say start at the pressure switches with an ohm meter, but i was waiting to find out if he even had a meter. if the pressure switches are closed, he has an electrical problem. If they are open, he most likely is low on refridgerant.

They switches do go bad, but its rare.

 

nipper

Hi Nipper,

 

I'm not sure what you mean when you say switches can give you a false reading. If a switch is bad and it supposed to be closed you will see a voltage drop across it. Unless of course something else in the circuit is open when it shouldn't be. Some tests need to be done when the system is live, so taking a voltage check is easy to do.

 

Hope you feel better soon.

yes i have a meter. where are the switches and relays located.

The evaporation thermoswitch is behind the right side of the dash, on the intake unit case.

 

The A/C relay is in the A/C relay holder on the left side of the engine compartment.

do i have to take the dash apart to get to it.

I don't think so.

the relays are good. i put relays from another car in it and it still didn't work. is their a way to test the wires at the compressor to see if its bad.

The evaporation thermoswitch is behind the right side of the dash, on the intake unit case.QUOTE]

 

i looked under there and didn't see anything. does anyone know if i have to remove the glove box to get to it.

Unfortunately my info doesn't have any pictures to look at for these things. I would send a PM to Legacy 777. If anyone knows, it would be Josh. Skip may know also.

 

To test the compressor you should be able to apply 12 volts to the main leads. There may be third smaller wire that is used for a pulse line to the AC control unit. Don't apply power to it if you do this.

couldn't i use my meter to see if it has power to the plug(not the compressor side). wouldn't that tell me the same thing. if it's getting power then the clutch is bad.