A/C comes on when on defrost and non-A/C fan.

TN.Frank · Post by **TN.Frank** » Sat Jun 07, 2008 7:14 pm

I noticed today that when I've got my settings on defrost, cold and turn the fan on(to the right, not the left for A/C) that the A/C compressor kicks in. What gives???

Danteneon · Post by **Danteneon** » Sat Jun 07, 2008 7:18 pm

That is normal. The A/C will cycle briefly whenever the defroster is on to help remove the humidity which causes the fogging of your windshield.

Paul56 · Post by **Paul56** » Sat Jun 07, 2008 11:06 pm

Yes, normal on the Neons.

I followed the instructions to mod mine such that the AC does NOT come on when the defrost is engaged.

I know I can engage the AC to remove excess humidity when trying to defrost the windows... I just like the ability to decide when that happens for myself.

Post by **occasional demons** » Sat Jun 07, 2008 11:59 pm

Paul56 wrote:Yes, normal on the Neons.

I followed the instructions to mod mine such that the AC does NOT come on when the defrost is engaged.

I know I can engage the AC to remove excess humidity when trying to defrost the windows... I just like the ability to decide when that happens for myself.

Pretty much normal on all cars. Do you have a link for the mod?
I have a switch set up to bypass the compressor engagement in all modes, but not just defrost. It comes in handy when climbing hills, or when you want a bit more umph taking off from a stop. If anyone's interested I would have to remove the HVAC bezel and see which wire I cut/installed switch, because it's been too long ago to remember.

Jerome Adams · Post by **Jerome Adams** » Sun Jun 08, 2008 12:37 am

it cuts out at WOT so just stay WOT all the time and you are good to go!

TN.Frank · Post by **TN.Frank** » Sun Jun 08, 2008 8:49 am

I would also be interested in the mod to stop it from coming on in the defrost mode.

gilly02le · Post by **gilly02le** » Sun Jun 08, 2008 12:43 pm

From the other .org.. used the be pictures, but not any more...still very simple tho
http://neons.org/howtos/ac-defrost.shtml

TN.Frank · Post by **TN.Frank** » Sun Jun 08, 2008 1:43 pm

gilly02le wrote:From the other .org.. used the be pictures, but not any more...still very simple tho
http://neons.org/howtos/ac-defrost.shtml

Thanks for the link, looks pretty simple.

Post by **occasional demons** » Sun Jun 08, 2008 9:18 pm

Hmm, wonder if that was wrote for a 1gn. Didn't mention that the two diffusers have to be removed and the two screws that hold the top of the bezel. If you just go yanking you may be shopping for a new bezel.

I like my idea of cutting the wire. At least it's easily reversable - but that's just me....

TN.Frank · Post by **TN.Frank** » Tue Nov 18, 2008 11:10 am

gilly02le wrote:From the other .org.. used the be pictures, but not any more...still very simple tho
http://neons.org/howtos/ac-defrost.shtml

I'm getting ready to do this mod ARE YOU SURE it's the bottom of the three that needs to be cut?

Well, I did it and it seems to work. No more A/C when the defrost is on. No more squeeky belt from having the A/C load the system. I've really got to get a Dayco 49" belt, the Gatorback 50" has stretched to the point that it squeeks like a little bitch when I turn on the A/C and they don't make a 49.5" in the Gatorback, which would be about perfect. I was told that the Dayco 49" belts are a tad longer then the Gatorback 49"(which wouldn't fit at all) so I guess I've got to get one of those.

Post by **occasional demons** » Tue Nov 18, 2008 12:00 pm

Just remember to cycle it every now and then, so it stays lubed. Sitting for long periods of time is bad for a/c systems. It is the other (main) reason they tied it to the defrost, to cut down on warranty repairs.

TN.Frank · Post by **TN.Frank** » Tue Nov 18, 2008 12:53 pm

occasional demons wrote:Just remember to cycle it every now and then, so it stays lubed. Sitting for long periods of time is bad for a/c systems. It is the other (main) reason they tied it to the defrost, to cut down on warranty repairs.

Yep, I'll remember. It also help the clutch to keep working too so it won't freeze up.
It's just with the "under sized" belt on the car it really makes a lot of racket when I put the defrost on because it was kickin' on the A/C and that was loading down the belt and letting the under drive pulley slip . Once I get the right belt on it I'm sure it would have been fine but still, I like having the option of putting the air on when I want it and not having the car be in control of that function.

Car6on14 · Post by **Car6on14** » Wed Nov 19, 2008 9:59 am

def going to do this mod this weekend, anyone change how it also switches to fresh air on defrost? Figure ill change that too, it felt mechanical so I thought I could just disconnect a linkage? this is on an 05 sxt...

Post by **racer12306** » Wed Nov 19, 2008 1:46 pm

Yeah, there are no electronics in their, its all mechanical switches. So that should be simple.