power windows by alarm

I was working on making my own window roll up/down module for any alarm with extra outputs.  Ive got all the basic wiring for it down with relays and such, but I needed some ideas on how to stop the circuit once the window it up or down all the way.  I know that there is a spike in current once it stops, what can I use to detect this current?  and how can I use it to stop the curciut?  Please advise

This is interesting. I am trying to work out a good way to do this as well . I'll fool around with it here at work when I get some time and try to get back to you.

I have installed window roll up, and roll down in several vehicles by using only relays. But there is a catch. I can only do it with an alarm with a "validity" output, such as a viper. this means that current is only on the trigger wire for as long as you are holding the transmitter button down. This will not work on the starter kill wire to rolll the windows up when armed. I have only done this with Viper alarms, and the only problem i had was occasionally blowing fuses upon roll up, which i solved by since installing a 30 amp breaker on the power wire to the relays. I have done this on a buick regal, chevy monte carlo, 2 full size chevy trucks, and a chevy suburban. Since using the circuit breaker, and only viper alarms with "validity" channel outputs, i have had no problems whatsoever. Some people might say this is "ghetto" but hey, its works fine for me! Why pay 50 bucks for a roll up module, when i can do it with 6 bucks worth of relays??