power window switch theory
Posted: Thu Oct 30, 2008 11:36 am
by marcusus
Can you explain in a bit more detail? I've opened up my old switch numerous times, as well as opened up my auto switch a couple of times too.
I would've thought that the non auto switch is a contact closure type of device in that you need to make contact for there to be power applied to the window. Once you move the white bit of plastic away from the contact, you shouldn't have a contact closure, thus you shouldn't have any power to the window motor?
power window switch theory
Posted: Thu Oct 30, 2008 12:49 pm
by marcusus
Yeah, I get what you're on about. The issue is getting the white plastic bits to stay in the position you've just pushed. The problem with that is that you'd need to mechanically find a way to do it by modifying the black switches themselves, or by doing it electrically by adding stuff to the PCB. I had a bit of a think about this before I bought my auto switch, and my thought process went something like this:
If you were to do it mechanically, how would you do it? You'd need to basically make the switch lock in the up/down position for a certain amount of time before it would then return to the "neutral" position. I don't know enough about mechanics to be able to make something that would do that.
The alternative mechanical method would be to remove the springs so that the switches don't spring back to the "neutral" position, but the issue then changes and becomes a question of how do you make the switches stay in the "neutral" position without the springs. Would the switch rest in the up/down position in this case?
Electrically, you could modify the PCB (without modifying the mechanicals) to be a "hold" type trigger, where a hold of less than, say, 5 seconds would result in the motor being active for the time you pressed, but a hold of more than 5 seconds would keep the motor on for the duration of time it takes for the window to go fully up/down. This, to me personally (I'm a computer engineer) is a lot easier to do theoretically than figuring out the mechanics, but it would also require a lot of time spent analysing the PCB and figuring out what does what. Then there'd be the time spent doing circuit analysis and figuring out how to create a circuit to create this hold effect. Then there's the issue of having all the newly soldered bits fitting in to the original housing.
In the end, it was much easier to just buy the switch. If you take into account how much your time is worth, going off what you get paid at work, it would probably still be cheaper to buy it.
Also worth noting is the fact that the auto window switches operate in a completely different manner to the non auto ones. The auto switches are a combination of a mechanical and electrical change to the device. The switches have extra toggle points past the standard up/down positions ie the up lock and down lock positions. The PCB has four points of contact on the switch rather than the two points on the stock one.
power window switch theory
Posted: Fri Oct 31, 2008 7:35 pm
by marcusus
yakob wrote:Conclusion, buy a new switch. Haha, thanks ;)
Yeah, pretty much. It's definitely the most time/money effective solution. However, once you've bought the new one, you could always pull apart your old one and have a play to see whether it can actually be done. If it can (and you don't mind working on it for like an hour a weekend for a few weekends), you can always offload your auto switch to someone.