window close from alarm without module

Hello, Mr car is very old (Porsche 944), which has a very simple electric window control system. The details can be seen here: http://www.clarks-garage.com/pdf-manual/elect-20.pdf ... but in essence the window switches are DPDT switches which connect directly to the window motors and cause the window to work in either forward or reverse polarity depending upon how long you press the switch for. There is no 'control unit' per se, and no relays either (the power for the window motors all runs through the switches). I have an alarm (Toad) which has function outputs, one of which is designed to connect to the electric windows. I have never connected this, but am thinking about doing so now. My question is, what is the most elegant way of doing this? The alarm output holds low for 20 seconds (although this can be adjusted up or down) and needs to switch as many relays as necessary to make the windows both wind up (it's a two-door car.) I can see that a popular option is to buy a window closure module, but I am not confident that these can be connected to a system as simple as mine; they all seem to offer more sophisticated functionality when connected to a car with a window control system - and I'm not interested in the extra functionality and don't have a control system to connect it to. Would the following circuit work? The windows need to remain independently operated for the rest of the time, hence the diodes. Would this do what I want it to do (wind the windows up when the alarm output goes low), and if not, why not? Thanks! Oli.

The more sophisticated functionality in the window closure modules is Anti-Pinch. The modules are current sensing so they know if there is an obstruction in the path of the window instead of just blindly rolling the window up.

awdeclipse, Thanks - I suspected as much. Some of them claim that they can detect obstructions in the windows so I guessed they were current-sensing. However, that aside, would my circuit work? What alterations or sophistications would you make to it? Oli.

Your idea won't work for the simple reason that the motor wires reverse polarity hence say goodbye to the diodes. Chuck the toad and get something decent or just add a DEI 529t, the Toad is compatible. And you wouldn't use the Toads function output (or aux output as it should be called) you use the armed output or Ground (earth) when armed. That function output is for cars with factory total or comfort close, BMW, Vauxhall, VW etc. Key in lock on driver's door hold to lock position, windows will rise.

This assumes the Porsche has type "A", motor wires NEG at rest, find the "UP" wire and use this diagram; it represents one window.:- raise_window.bmp The diode shown is a 1N4004. NOTE I don't advise using this method as sooner or later you will burn out the motors.