I'm sure that this is a VERY petty rant , but WTF, why is it when you press the defrost button on a '99 LTD, while having the heat all the way up, the A/C comes on?? Its just annoying, 20 degrees outside, my window is frosted, why would I need my A/C on full blast? Drives me crazy because sometimes I think I hit the button to turn it off, but with gloves on I miss, then 40 miles later I notice it. Great for fuel economy I'm sure...


I'm assuming that there was some logic behind this, I just don't get it, so if someone would enlighten me that would be awesome. I will then to your wisdom. [/rant]


(I'm going to feel really stupid if this is an easy one....)

 

lots of car companies do this now. the reason is that the a/c is supposed to help dry the air to make it easier to defog. my '99 subaru does it too. i understand why they do it, but i'd rather it be left up to me. i know if i want the a/c on or not, i hate trusting everything to someone else's propiatory decisions .

mike

 

The a/c shouldn't make it run colder. It helps remove the moisture from the air as stated above.

 

Yup, it removes the moisture out of the air.

 

Also, the AC system needs to be turned on every month for matainance. Without this feature you would never turn it on all winter.

 

Most if not all American vehicles have done this for a very long time.
You just don't notice it because there isn't an A/C light.

 

The A/C system runs through a sytem to collect moisture. So once the heat evaporates the moisture inside it helps to capture and release it outside your vehicle. That is the puddle under your truck on the passenger side.

 

Wow guys, thanks for the responses. I figured that it would end up being something that simple. :pat: Its funny but understanding something so basic is going to make my morning routine so much less annoying.

I love learning new stuff, thanks Yotatech!!

 

Used to have a '98 RAV, which was the first Toy I had with the "turn the defroster on, kick on the A/C automatically" feature, so I asked the stealer about it at the time of purchase. He said in addition to the drier air, the A/C used a "heavier duty" blower motor, so it cut down on wear and tear when on high... not sure if he was just blowing smoke to make the sale (it was already a done deal anyway) or if that was actually the case.

Now with the Taco, I generally kick the A/C on myself when starting her up in the morning to help keep the moisture level down and the blower level up to clear off the windows that much faster.

 

Don't feel bad. My 97 Tacoma does it and I wanted to ask the same question, I was just too embarassed to. I am very economy oriented and I make sure to turn it off when not needed, but it bugs me too. At least I now know why it comes on.

 

jaja i learned this a few yrs back. the a/c is just dry air, just make sure you got the warm temp on and it will defrost real fast.

 

used to do it myself in my old nissan to speed up defoging

 

On 96-97's with the "slider" style controls, you can slide the lever just slightly to the left of the defrost position and it shuts off the A/C. It's kinda silly to turn off the a/c..but it works. I've also noticed that if I drive with my regular heat on with the A/C button on too, the interior doesn't get a musty smell, and the floor mats dry faster.

 

This thread delivered.

Thanks for the answer. I wondered why the a/c light was staying on.

 

and if you have a limited w/ the climate control, you can hit the defrost button, and then hit the AC button to turn the AC off. however, it works better w/ the AC on to dry the air...

 

Concerning 1999's - On the back of the control their is a wire that sends a signal to the ac when you set it to defrost. Just unplug the wire and tywrap out of the way and you can control your defrost like you want. You have to pop out the center console to get to it but that only takes a few minutes.

 

Whats the deal with circulating the inside air??? Does this allow any outside air in or are you just blowing around stale air? Anyone know when it should be used and what for? Mike

 

I use the recirc button all the time. I don't like being stuck in traffic smelling exhaust fumes. I turn it on when I smell a skunk or am behind an oil burner. It is one of my favorite features. I will also warm or cool thew air quicker because you are not pulling in colder or hotter airt from outside.

Matt

 

for MAXIMUM cooling in the summer, you use recirc.

 

It is a nice feature! I have a Jeep with a separate A/C unit and it is very hard to un-fog because the A/C air does not pass through the defroster.