How do I Make a timer circuit?

Ok here is the deal,

I want to make a timer, that is triggered by a negative input. I need this timer simply to take the negative input, and apply a negative signal to a factory window roll up/ down system. The way the factory system works is, I apply negative signal to a specific wire, and the windows wil start to go down after a few seconds. The windows take lets say 10 - 20 seconds to go down. then I want the timer to stop. I can do the same to another wire and the windows will go up. (this can be accomplished by using the key int he door lock and holding it until the windows go up if locking, or hold it untilt he windows go down if unlocking. Since I have an alarm system on the car, I want to somehow tap this system to add window roll ups to the alarm system without using a module.

Is there a way to make something like this using relays, diodes and resistors? and if so, how would I do it?

I have a dei 530t I have not installed, and I do not think it will do what I want it to do. I have a 5 channel alarm system. I am going to use 1 channel for remote start, and I want to use another channel to trigger this wire that makes the window go up for a specified amount of time. I may also want to do the same thing to the other wire that makes the windows go down. also this same wire that makes the windows go up or down when a negative signal is applied also arms opr disarms the factory alarm system depending on which wire is grounded. (the ground to arm and disarm the alarm is just a simple touch it to ground and remove it from ground and it activates or deactivates the and the factory alarm activates. so I have 2 wires, I hit one with a ground and then remove the ground tivated. I hit the other with a ground and take it off ground and the factory deactivated.

I need to build some kind of timer circuit that will keep the relay on until the time has run out then cut the power to the relay. I would prefer to not use a window module as the car does not need to have the windows wired up the way a module does considering the factory system can roll the windows up or down by simply grounding a wire for a period of time.

Please let me know, I don;t mind buying a timer unit, but would prefer to make up one myself if I can.

Back before we had these window modules like the DEI 530t, they must have been done with home made timer circuits involving relays, diodes and or resistors am I correct?

So if anyone knows how I can build a timer circuit, it would be much appreciated.

AshMan

Yes I know about the 528t. I can probably use the pulsed output of the alarm system to trigger this built in car feature as long as I press the button.

I was hoping to make it a simple hit the button and it does its thing kind of deal.

AshMan