SAAB 9-5 Window Control Module Modifications

The abilities of the window module are very basic - just wind the windows up and down, when the ignition is on. Not much else.  But WE WANT MORE :)

So it has been suggested that maybe a system could be implemented to wind the windows up when the doors are locked via the remote.

The window control module already has a timer circuit built in which allows the front windows to wind up with just a tap on the button. We can use this function to be triggered by a pulse from a micro to wind the window up.

The next step will be to find the right signal to trip the window UP command.

I suspect there will be a lock command on the I-Bus which could be used or it might be possible to take a signal direct from the from the TWICE module as it is located under one of the front seats.

Having a poke around in the TWICE module I would be looking for the output from the remote receiver and seeing if I can easily differentiate between the lock and unlock signal. This must be a signal that is only present when activated via the keyfob and not say a lock button in the car or the auto lock function.

If Cracking the TWICE module open proves to distressing the I Bus may have what We need as well but with added complexity of decoding and filtering CAN data.

Some usefull information on the I Bus I have found at http://pikkupossu.1g.fi/tomi/projects/i-bus/i-bus.html#720 while specifically for a 9-3 I would take a punt that there would be sufficient similarities for the data to be useful.

We would need to provide power as well to the window module as its power is cut when the ignition is turned off. Power for the Central locking is routed through the TWICE module which is supplied by a 30A fuse which would be possibly be suitable for the windows - maybe with a slight delay to activate the window after the doors have locked to prevent excess current draw.

After scouring through the SAAB Workshop Information System I finally found the wiring diagram for the Windows. Funnily enough not located in the wiring diagram section but under

• Body
  • Glass, windows and mirrors
    • Electric window lifts

1. NC
2. Rear Right 1
3. NC
4. Illumination in
5. Rear Right 2
6. Front Right 1
7. Front Right 2
8. Ground
9. Rear Window lock (12V active 0V locked)
10. NC
11. 12V in
12. 12V in
13. NC
14. NC
15. NC
16. Rear Left 1
17. Rear Left 2
18. Front Right 2
19. Front Right 1

The SAAB 9-5 windows are solely under the control of the window control module independently of the "computers" in the car. It is not much more than 5 mechanical switches a relay and some minor analog circuitry.

Functions:

1. windows up and down via switches
2. over current cut out
3. press down for a short period and the window goes all the way down.(front windows only)
4. lock out switch to disable rear windows so the kids cant play with them.