hey guys, has anyone found a creative way to make the rear defroster stay on by default? getting cold as $hit up here in the NW, and it would be ideal to have this set on by default. save me some time in the morning with remote start and all.

should I hit up KP tech to see if they would be interested in designing one? am I totally missing an easier way to do this?

 

I was about to say how hard is it to hit the button but I see what your saying. You could hot wire it but then it would run all the time which isnt a good idea. You could hook it up to an aux switch and flip it before you leave the car the night before

 

It's not as simple as a switch. Remember that it is on a timer, pressing the button starts the timer and it stays on for about 15 minutes. It works that way for a reason - safety related most likely.

 

There is a blue/red wire at Pin 9 of the BCM (drivers kick). This wire reads 5vdc normally but drops to 0vdc when you push the defrost button. Find this wire and check to see if it goes back to 5vdc as soon as you let the button go or if it stays at 0vdc until the defroster shuts off.

If it goes right back to 5vdc as soon as you let it go (which is what I would expect it to do) then you can pulse this wire with the factory alarm rearm output of your alarm (I believe it is a green/black wire). When you arm the car, since it isn't running, the defroster shouldn't turn on, but each time you remote start the car, after it starts, the alarm will output a pulse on this wire, which will turn on the defroster. This is probably the easiest way to do it. If you are concerned about defroster life you could install a summer/winter switch inline!

 

thanks for chiming in all. I'll let you know how it goes when I get around to it.