(long) Re: remote locking sends power windows up

[Elliott Potter <epotter@abraxis.com>]

>
>Fellow Listers,
>
>If anyone cares, my understanding of automatic window/sunroof
>opening/closing is this:
>
>1.      Within the "rollup/down unit" there is a sensor which senses an
>increase in current draw.
>2.      When the "unit" is triggered the window motor gets power (up or
>down).
>3.      When the window is all the way up, the motor begins to draw more
>current,        trying to go further.
>4.      The unit stops providing power to the window motor and resets.
>
>If the windows are already up, all the motors still momentarily try, but
>the unit switches off because the current draw is above a certain
>threshold.
>
This is very helpful.  Do you happen to know what the actuator for the
remote locks does?  When the button is pressed on your key, what does
the
alarm system do to tell the locks to lock?  I had guessed a 5V pulse but
I could be wrong.

>It is easiest to just buy a unit that does this from any shop that
>sells/installs car alarms.  One particular brand that comes to mind is
>Clifford Electronics.  Or, you can check in a J.C. Whitney catalog for
>all kinds of these units.  Expect anywhere from $40 to $80 dollars for a
>unit.  You may need two units for a four door or for both one-touch up
>AND down.
>
This would definitely be easier.  I had not known these existed.


>Anyone with one-touch down should notice the lights dimming momentarily
>when the window reaches the end of its travel.  That's when the motor
>starts straining to keep going and the circuit shuts off.  Personally,
>I've never though this was very good for the motor, but I guess the
>automakers don't seem to think so.  I even think some crappy American
>cars have a switch that clicks down when you press it all the way, and
>when the increase in current draw reaches a certain point, it heats up
>or something and pops back up, like a cigarette lighter, thus stopping
>further travel.  No offense to anyone, but a Chevy Beretta comes to
>mind.
>
hehehe...
Reminds me of the 95 Jeep Grand Cherokee; this car was almost brand-new,
the battery was fine, the voltmeter was showing right around 14V.  I
was sitting in the car waiting for someone and was bored; I fiddle with
things when I'm bored so I pushed all the window switches up and held
them
there.  I glanced at the voltmeter and noted it was now at about
13V...12...
10...
At 8V a warning light came on and it started beeping and this stupid
screen
told me to "Check battery"...
Thought it was kinda amusing...

>[...]
>
>I think we Audi owners are used to spending a little money in the
>interest of something cool and convenient.
>
hehe
excuse me...
BWAHAHAHAHAHAHAHAHAHAHAH!!!!
<sob!>

>I just wanted to explain something that I've always taken as fact from
>observing my cars.  I don't want to see someone adding sensors inside
>their doors to detect the position of the window.  BTW, if you close you
>arm in a window going up on its own, it'll prolly hurt, but it'll stop. 
>But if you have a sensor that won't stop it until the window is actually
>up, you'd have to wait for the motor to burn out, or the battery to run
>down, or a passersby, or stretch yourself to the battery to disconnect
>it.  Not my idea of fun!
>
In fact, this had not crossed my mind, but now that you mention it it
seems
that it's a pretty important detail; if I were to still do this project
I would definitely try to connect it somehow with the related sensor
(the
one that senses the current draw of the motor).  I agree with you
totally
here.


>No financial interest in anything, just don't want to see any Listers
>make things more complicated than they need to be.  Of course, if you
>were into solder and diodes and stuff, feel free, I'm just lazy I guess.
>
If you're into this sort of thing and would like to design a circuit to
do this you probably could make one that was $80 or so that would
control
all 4 windows.  I think, however, that if you aren't feeling creative
enough to spend a weekend installing and troubleshooting a home-made
device I would definitely go with the premade units he mentioned above.

>[...]
>No offense to anyone else's suggestions! :-)    And sorry for the BW!
>
I'm glad you brought this up!  And don't apologize for BW usage unless
you're talking about: (couldn't pass up the opportunity to post this
gripe...)

1-synthetic vs non-synthetic oil
2-headlights
3-speed laws in the US
4-other laws in the US
5-Fords
6-Any cars except Audis

Thanks again!

Elliott