W124 estate electric windows

[wilfy]

I have a weird electrical problem. My electric windows on my 230TE will only work with one of the front doors open! The problem is somehow connected to the courtesy light switches in the front doors. The windows will shut when using the door key in the usual way and the sunroof is not affected. There was no warning that something odd was about to happen it just started this afternoon. Disconnecting the battery for a while had no effect. My wiring diagrams from the Haynes manual are hopeless and don't show any sort of control unit, although I presume that there is one somewhere. Any ideas as to where to start would be very gratefully recieved.
Mike.

 

[turnipsock]

If there is a control unit it will be under the N/S rear seat.

 

[C220GJS]

Have you checked all your fuses ; the windows working when the ignition is off and the door open is normal ,also the total closure system works when the ignition is off ; so I would suspect the window circuit is not getting power when the ignition is on.

 

[wilfy]

Thanks for your help. I get your point but the problem seems to be more complex than this. If I press and hold a window switch with the door open the window will operate BUT if I then press the courtesy light door switch in either front door the window immediately stops! If I release the door switch the window winds again! All fuses appear normal. Opening the door to operate the windows is becoming a pain!
This happens with the ignition on or off.

 

[Blobcat]

When the door is open and you open/close the windows does the interior light dim slightly? I thinking that possibly there is an earth/power connection problem to the window motors. And that they are earthing through the interior lghting circuit.
I would take off the door cards and check the wiring to/from the motors and the flexible connection at the door hinge.

 

[wilfy]

w124 windows

No the light does not appear to dim but the flexible connector at the door could be a likely first place to start. What I cannot understand is the relationship between the courtesy light switches and the window motors. Also I have never had troubles with either of these circuits, or indeed any circuit on this car before, and I have owned it for quite a while now.
Many thanks for thinking about this - I am now worried about the MOT which is due in a few weeks and what will be the outcomer if I produce a car with no opening windows. Is that a fail??

 

[G MAN]

As stated above that's how they are supposed to work & will stop if you depress the coutesy switch in the door post whilst trying to operate. Are you saying they don't work with the ignition on as this would be your only problem?They won't operate with the door shut & the ignition off. Try to reset by turning ignition on & holding the rocker switches down in turn down for a few seconds at the end of the travel, you may hear a soft click. Also check the child safety switch by the gear selector that prevents the windows from being opened by the switches in the rear doors. Its all a process of elimination. again as stated by C220GJS check & clean all your relevant fuses & lugs they are known to be problematic (in severe cases the wiring entering under the fuse panel can melt) Otherwise wires do break in the flexi connectors in the doors & this again is a process of elimination.
So if they work with the door open ..fine & with the ignition on but doors shut...fine.But not designed to work with doors shut & no ignition.

 

[G MAN]

BTW how did this thread end up in Spares for Sale?

 

[wilfy]

124 Elecric windows

With ignition on the windows will only operate when a front door is opened enough to make the coutesy light switch on. Wiring looks perfect in the area between door and body but I haven't had time to take off the door cards yet. Rear windows don't work either unless either front door is opened. Also, with ignition on opening a rear door has no effect - they don't work until one of the front doors is opened. AAARGH!

 

[turnipsock]

Try taking the courtesy light fuse out and see if things change. Might be fuse 9 but I'm not sure.

I think Blobcat is onto something.

You can also take the door cards off and check the voltage on the motor.

Do you have puddle lights on the front doors and not the rear?