A/C Compressor Clutch Engages with Heat on...?

[97Ranger3.0]

Hi everyone,

So I recently fixed my non working A/C in my 1997 Ranger. I had to replace the compressor and got the system recharged the other day and it now works great. This morning though, I went to turn the heat on as it was a little chilly and I thought I heard that subtle 'click' sound when the A/C compressor clutch engages. So I popped the hood, turned all the HVAC controls off, the clutch is not engaged as you'd think. Then I turned the blend knob to full heat and turned it onto the first setting to the right (blowing from all vents) and what do you know, the A/C compressor clutch engages. That just does not seem right to me, I don't see any reason why that should be happening. So my question is, is that supposed to happen? I wouldn't think so but maybe I'm wrong. And if it's not supposed to happen, what could be causing this?

Thanks!

 

[Uncle Gump]

It is suppose to happen... turning on the A/C is done to dry the air of moisture.

 

[97Ranger3.0]

It is suppose to happen... turning on the A/C is done to dry the air of moisture.

Huh, I didn't know that. I guess you learn something new every day. So my next question then is, does anyone have a wiring diagram for either the HVAC control switch or the A/C system in general? The reason I ask is, I have an electric fan in the truck and when I fixed my A/C I added a manual switch to turn the fan on high speed because I thought I would only need to turn it on when I had the A/C running. So I would now like to re-wire it so that the fan automatically kicks on when the A/C compressor clutch is engaged. I'm imagining I should be able to tap into the wiring that plugs right into the compressor, I imagine one of those wires is the power and one is ground for the clutch. I'll see if I can figure it out with a multi-meter, if not I'd definitely appreciate some advice!

 

[ford4wd08]

Also, running the defrost is dependent on the AC compressor too.

 

[Josh B]

I found on my 93 that just going half-way into defrost will dry your windows and not engage the a/c