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Discussion Starter #1
So if you switch your air vent dial (from upper vent/floor for example) all the way over to the window defrost/defog option, the condenser is clearly turning on -- despite the fact that the AC button is not lit up.

My previous car, a Ford ZX2 did the same thing and it drove me absolutely nuts. Mainly because that thing was nearly un-drivable with the AC on. Zero power, and the condenser would cycle every 5-10 seconds causing a very noticeable jerk in the vehicle. Thankfully, this auto-on disables when the climate gets cooler.

Now, the power loss is less of an issue with my 3, but I still don't like it. Let the user control if the AC should be on or not! The AC light should flip on and give me the option to press it off. It's 59 degrees and rainy here. My clothes are wet, I want to clear up my windows, and not shiver to death.

Any knowledgeable folks know how to disable this "feature"?
 

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So if you switch your air vent dial (from upper vent/floor for example) all the way over to the window defrost/defog option, the condenser is clearly turning on -- despite the fact that the AC button is not lit up.

My previous car, a Ford ZX2 did the same thing and it drove me absolutely nuts. Mainly because that thing was nearly un-drivable with the AC on. Zero power, and the condenser would cycle every 5-10 seconds causing a very noticeable jerk in the vehicle. Thankfully, this auto-on disables when the climate gets cooler.

Now, the power loss is less of an issue with my 3, but I still don't like it. Let the user control if the AC should be on or not! The AC light should flip on and give me the option to press it off. It's 59 degrees and rainy here. My clothes are wet, I want to clear up my windows, and not shiver to death.

Any knowledgeable folks know how to disable this "feature"?
Well, the A/C is designed to turn on because it dries the air that is blown over the windshield. Not having the A/C automatically turn on would probably dramatically decrease the effectiveness of the defroster. Although you're blowing air over the windshield, its ability to carry moisture off is weakened, or maybe completely counteracted if the air is humid.

I know that you can turn on the A/C and have it on "hot" and the air that is blown will still be warm, but extra dry. Have you tried that when defrosting, to see if you get dry A/C air that is still hot?

As for your question, though, sorry, but I haven't read anything about disabling this feature (doesn't seem to be in the manual).

--Garfield3d
 

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I'm not sure how to disable it, but the AC dehumidifies the air. Where I live it's humid enough that if I turn on the defrost without the A/C my windows actually get foggier...some times fogging up the entire car! This happens in most temps above freezing.

You can adjust the temp if it's that cold and still take advantage of the dehumidifieng of the A/C. You'll just get warm dry air blowing against the windscreen.
 

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Discussion Starter #4 (Edited)
Yep, it does get warmer if I turn the dial over. It just weirds me out having warm air come out when the AC is on. But the humidity issue never really occurred to me. I only get window fog when it's cooler out and rainy (or freeze-your-balls-off arctic), in which humidity isn't too much of a problem.

I assume this will disable when it gets to be something like 45 F or cooler like my previous car.
 

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One 3, one 7, one fun!
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Most cars (most from what my experience has been, anyway) are like that.
I remember I found a "how to" to disable it in the Neon I used to have. It involved to take the AC panel off and drill through a flat electronic type of board t kill the connection that made it go on.

Two things:
1) Most of the times the help from the AC is really not necessary. Windshield fogs up because it is cold, warmed up air from outside will be very dry and therefore the defrosting will work just fine. Problem happens when you are in very particular situations (I give you one of those I tend to run into the most): you take 3/4 people in the car who have just finished playing a soccer game in the summer. It is raining hard and you can't open the windows. Your windows fog up and since the temperature outside is fairly high, your defroster is having a hell of a time without having the air on.

2) This feature can cause problems. My wife took my car once and drove it to her friend. On the way back, she had the air on and the windshield started to fog up... on the outside! This is because blowing darn cold air to the windshield cools parts of it down dramatically, recreating winter conditions perfectly, but in a reverse type of situation. Her being completely oblivious to simple physics and elemental natural phenomena, made the situation a complete nightmare for the entire time she was driving back home.

I think that you should be the judge as to when to use or not use the AC in conjunction with defrosting.
Makes sense in certain conditions, but I agree, it is an annoyance in most cases.
Especially if you drive manual tranny cars that don't come with 500 ponies...
 

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Yep, it does get warmer if I turn the dial over. It just weirds me out having warm air come out when the AC is on. But the humidity issue never really occurred to me. I only get window fog when it's cooler out and rainy (or freeze-your-balls-off arctic), in which humidity isn't too much of a problem.

I assume this will disable when it gets to be something like 45 F or cooler like my previous car.
Yup, I think it does.

In reality, I don't think the A/C needs to be on in all conditions (unless you live in Houston).
 
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