Those window controllers look seriously expensive. I can see why the previous owner/s tried to bypass it. Not sure about the 456, but on the "M", there are wires which go between the Window Controller and the Door Lock Module/Controller. I'm not exactly sure why. When you open the door a switch in the door latch sends a signal directly to the Window Controller to drop the windows. I guess both boxes need to know the state of the door latch. The M has an indentical looking box (different part number), but it isn't in the doors and there is only one box.
thanks for the info. I am guessing that the door boxes are needed for the central locking as well as for the windows on the 456GT. I'm tempted to open up the box I have to see what the circuit is like, but replicating that would be a bigger project than I want right now.
Not really sure about the 456, also... After revisiting the 456M circuit... I have to correct that statement. It's the interior and exterior door handle microswitches which trigger the window drop, not the latch sensors. The doorlatch position sensors, which also feed into the Window controller, are used to inhibit locking (with either door unlatched). Anyway, coordination is required between the door and window modules. I guess you could still open the box just to see if there are any burnt components. Does the 456 (non-M) have the window control function which adjusts the window position when the car is at high speed? I can't imagine that function will be easy to replicate.
The right door box had been removed before I bought the car, otherwise yes, certainly I would have opened it to see whether I could fix it. I will as the last two previous owners whether they have it, but I think that it was removed by the butcher of an electrician who mangled the wiring in that door. I'm looking for a right door loom, part number 153104, if anyone has one going spare...
The Door/Window ECU are the same between sides, and can be swapped on the 456GT, the 456M only has one door/window ECU. They seam to be pretty rare, or very expensive if you do find one. This will be why the central locking is not working. The ECU has several in puts to control the window. Upon opening the door, the inside(and Outside) door handle have a micro switch which drops the window down 10-20mm. The fixed door catch (car body) has a micro switch which closes the window when the door is shut. There is a speed signal from the main engine ECU when over 110km??/hr blips the window closed. The ECU also senses an over current to set the Upper and lower window limits. (This is all I have identified so far).
Thanks. This was one of the pieces of the jigsaw puzzle I was missing. I was earlier thinking that it was one of the sensors in the latch (lock) that raised the windows. I thought the door pillar/catch switch was only for interior lights and door open indications, but I do see there is also an input into the window control unit. The 456 (non-M) WSM labels the door pillar switch as a "Window control emergency sensor". Is it possible that the door latch mechanism is also a trigger for "windows up". Can you confirm that, with the door open, if you trigger the door latch with a screwdriver, latching the mechanism, i.e. simulating a closed or closing door, that the windows don't go up? (EDIT: the 456M WSM confusingly labels the same switch as an "Open door sensor by lock")
Thanks for the information, both of you. In my car, when one of these units failed, whoever 'fixed' the problem removed the unit and butchered the door wiring to get the window switch to work, but of course with no central locking and no auto-lowering. This means that the passenger window has to be manually lowered and raised to shut that door, which is only ok if you never carry any passenger. I've now found a replacement wiring loom, but I'm not going to pay thousands for a door control. I suppose the reason no-one has come up with a third-party solution is that the low volume makes reverse engineering a box not worth it for a manufacturer, but with the ridiculous prices they are going for, it might now be worth it!
Hello, there are two door pillar switches, one is for the interior lights, the other which is part of the fixed door jam catch has a small black switch, this is the window close switch (When the door closes),
Does anyone know of a compatible unit? I haven't seen anything of the sort. I'm sure one could be engineered.
I very much doubt any other unit will be a straight swap. They're not complicated devices (input for door latch and lock signals, output for window up/down), so it'd just be a question of finding the correct wire schematic.
Yes, I agree. I am seeing absurd prices of several thousand euros/pounds/dollars being bandied about for these boxes, used. I haven't opened the one box I have, yet, but I imagine it will not be very complex circuitry. I'm a physicist, not an electronic engineer, but I imagine that the 25 to 30 year old electronics inside cannot be so difficult to reverse engineer. If anyone on here runs a small electronics company it would probably be worth your while to make a small run of boxes to sell to 456 owners. Please reply or send me a message if you know of anyone. If no-one on this forum wants to do that, or knows someone who might be interested, I'll look around for someone who might do it.
