3500 LX9 A/C wiring help

[americasfuture2k]

what are all the wires that go to the A/C compressor? color of wire, what each wire does and where to get new connectors. all i need now i believe.

[IsaacHayes]

Should be 2 wires just to the clutch. Unless you are referring to the pressure sensor in the line as well.

[americasfuture2k]

everything that goes to the compressor. im trying to wire it up to my fiero harness. the clutch line was easily identified. but i have 2 other single wire connectors on my fiero harness. those are being identified. i need to know what the other wires are that go to the compressor and where to get the new(or used) connectors to spice my wires into.

[IsaacHayes]

Well on my car, has 2 wire plug for the clutch, and only other connector is a 2-wire pressure sensor in the hot side of the line. Not sure if that helps or not, sounds like it's a funky setup on the Fiero maybe.

[americasfuture2k]

i think hte fiero setup is funky, ill get back with you when i get what each wire/connector is/does

[Joseph Upson]

i think hte fiero setup is funky, ill get back with you when i get what each wire/connector is/does

Are you using a Fiero compressor or the 3500 Compressor? I suspect the 3500 compressor which only has a clutch terminal that would leave you with two loose connectors one of which gets a pressure signal. You should be able to find detailed info on the Fiero forum regarding it, I haven't connected mine yet but understand the late model compressor automatically makes adjustments allowing it to run continuously instead of needing to cycle.

[americasfuture2k]

here is what blacktree on PFF said:

Originally posted by Blacktree:

The one with the black wire is for the high pressure cut-off switch. That black wire is actually the ground wire to the clutch. The dark green wire with the white stripe activates the radiator fan. It's the ground wire for the fan relay.

Also, the receiver/dryer has a low pressure cut-off switch in it. It has two wires, green and blue if I remember correctly. This switch sends the "A/C on" signal to the compressor clutch relay.

im using the 3500's compressor. ah dang, but wouldnt that be the ECM that adjusts it so it doesnt need to cycle? wouldnt it still work if it was cycling?

[Joseph Upson]

here is what blacktree on PFF said:



im using the 3500's compressor. ah dang, but wouldnt that be the ECM that adjusts it so it doesnt need to cycle? wouldnt it still work if it was cycling?

From what I recall reading on the Fiero forum the compressor is self adjusting due to its internal design which is probably why one might think it was broken if you put your hand over the ports and turned the hub, where unlike the Fiero compressor, you will not notice any compression or vacuum. You can set it up to work like the Fiero compressor by adding the missing sensors up front at the accessible fittings.

[americasfuture2k]

explain more on this subject please. i know nothing about this compressor or the fiero compressor. like what sensors? and what accessable fittings can i fit those sensors onto?

[Joseph Upson]

explain more on this subject please. i know nothing about this compressor or the fiero compressor. like what sensors? and what accessable fittings can i fit those sensors onto?

You will have to look up the related threads on pennocks, I didn't notice anything difficult enough to make it worth saving the link. You have high and low pressure valves up front in the spare tire compartment that "T" fittings can be added to replace the missing terminals on the newer compressor. There is a pressure sensor on the dryer that can be tapped into and you should also have some control through ECM settings. You need to look at the wiring diagrams to have a good idea of what to do.

I have not wired my compressor yet although it is on the car. The pressure sensor basically protects the system from damage due to improper refrigerant levels. To low and the compressor will not cycle on, I haven't spent time reviewing the wiring diagram yet.

[IsaacHayes]

If the 3500 compressor has just a hook up for the clutch, you should be able to wire in like stock.

Some older compressors like the 2.5L ironduke had some sort of varible compressor I thought. As far as I knew though it worked like the old ones just 2 wires for the clutch.