Electric windows.

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Geoffrey Gould
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Electric windows.

Post by Geoffrey Gould »

As above something funny is going on, front electric windows ( no rear) all working and then the drivers side works ok, it has the 4 part switch - up down and one touch up and down if that makes any difference, the problem is with the passenger side window. The switch on the drivers door for the passenger window does nothing, the switch on the passenger side makes the window go up and not down.
Hope you can follow that, the motor is ok, the wiring from both doors to "A" posts is ok. It seems to have lost a feed or earth somewhere, fuses are intact, relays and switches changed. Cant make head or tail of the H****s wiring diagram. Any sugestions, apart from setting fire to it, as regards where to start. I have a gut feeling its a bad or high resistant joint. Im hoping its not the fuse board as have had more than one burn up.(not on the same car.)
Thank you gentlemen for any help you may be able to give.
Cheers.
Geoff.
st gilles

Post by st gilles »

I've had this sort of thing in the past with mine and found it was bad contacts in the switch. Have you tried 'digging' the switches out with a very fine bladed screwdriver and swapping them over or if you have a spare one then just swap it for the offending article. Failing that (cos I'm not sure if the 'one touch' switches are interchangeable with the normal ones).........take the switches from both doors out and seriously swamp them with WD 40 or the like and work the switch vigorously. :oops: There is a special spray for cleaning electrical contacts from Maplins but I found that the WD40 worked for me. This made all my 'leccy' winders work and is something I now regularly do on mine as it lives in France and I don't, so is left unused for long periods.
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Way2go
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Post by Way2go »

Looking at the diagram on page 13-53 and legends on page 13-56 it would appear that what they say is LH (No 76 Electronic Control Unit) is our drivers door and what they say are RH (switches 519 & 521) are for the passenger door)
The passenger door is non electronic and relies therefore only on switch logic! Your problem therefore most likely is because one of the switches is not connecting in its rest state. I would suspect the passenger switch in the drivers door as you are getting operation in one direction when switching the switch in the passenger door.
Meter the connections or check by switch substitution.
1991 BX19GTi Auto
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saint gaz
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Post by saint gaz »

In the past i had a similar problem. Actualy traced it to a break in a wire from the drivers door in the rubber tube thing. i just soldered a thicker wire in place and worked ever since.
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Geoffrey Gould
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Electric windows.

Post by Geoffrey Gould »

Hello thank you all. Well still pretty foggy about what is going on. Metered the passenger switch and found 1 supply 12v+ the rest were about .2 to .25 of a volt and wandering all over the place.(digital meter.) removing the drivers side switch cut the 12v supply.(NS swt).
Noted that Way 2 Go says that the switch has a rest position, well in that position all tags on the switch are open circuit.
Tried to get clever and swap the polarity over by linking the tags on the passenger switch and what I found was that if I held the switch in the "down" position (NS swt) and just flashed conection fron pin1 to pin 3 the window would open if I left the connection on it would draw a lot of current as in short circuit.
Gave up Im affraid getting very very wet, both me and the car inside.
If you dont have one touch operation then there is no "black box" in the OS door, just thought I would throw that in for good measure just to make sure that I wasnt the only one to be confused.
Cheers
Geoff.
PS. The car went to France, boose and fags trip,the passenger window remained closed,bummer,was completely dismantled by the customs on the way out,"quote BX's are one of the best cars for smuggling dope etc." Thank you Mr Customs :twisted: thanks to you was 3 hours late and missed the ferry and had to reasemble the car. On the plus side 57MPG, 609 miles didnt miss a beat. We still love you.
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Post by jeremy »

just to confuse matters still further I have a sticky motor on my BX TD - and usually on holiday the window will stick down. Easy to avoid - just don't lower it too much but getting it up is not quite so easy! - but every time I get it de-trimmed it starts working nicely.

I think there may be a thermal cut out in the motor - or its got a sticky brush but basically if I thump it it works again.

The passenger window circuit is rather complicated to allow for the switch in the driver's door. The switches don't last well - and I've had to clean mine several times, and of course the driver's door switch operates the window more slowly due to the length of cables. The favorite is for the cables to break where in the section passing through the rubber tubes into the doors.

I would start with the motor - which has 2 connections - feed one way it goes one way, reverse and it should go the other. Having established the motor works - I'd then work backwards but making sure that I put everything under load as soon as power was established.

What I mean is that you will probably have a battery voltage of 12.5 volts at the battery dropping to 12 or evevn a bit less at the door. Using a digital meter its easy to get 10 or so volts but as soon as a load is put on it it dissappears which is obviously not what you are looking for!

jeremy
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Post by silverfox »

[quote="saint gaz"] Last year I had a similar problem. Actually traced it to a break in a wire from the drivers door in the rubber tube thing.

I had exactly same problem last year and a wire had snapped inside the insulation. Was taking so long to trace it a fresh loom was installed! (The broken wire was found at a later date) :o( Geoff
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Re: Electric windows.

Post by Way2go »

Geoffrey Gould wrote:Noted that Way 2 Go says that the switch has a rest position, well in that position all tags on the switch are open circuit.
If this is so then your switch is faulty as the electrical logic requires earth (- supply) paths through the switch when it is NOT operated. This also goes for the door switch. Remember that you are looking for earth continuities and not + 12 volts. (when the switch is NOT operated there will be only one pin on each of the passenger switches where you should measure + 12v)

Two contacts on the passenger drivers door switch are fed with earth and one with +12v. The passenger door switch is fed with only + 12 volts directly and it derives its earth feeds via the passenger drivers door switch.

The circuit works by lifting one side of the motor off earth via the switch and moving it to +12 to operate in one direction. Moving the switch the other way lifts the other side of the motor off earth and applies it to +12volts to acheive operation in the other direction.

You cannot try jumpering 12volts to test operation because normally both sides of the motor are connected to earth so sparks would be expected.
Clearly if you have any broken wires the circuit wont work properly as the logic is then defective let alone the supply current.

Hope this clarifies and helps
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Geoffrey Gould
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switches.

Post by Geoffrey Gould »

Well done that man Way2go yes that makes sence so begging your indulgence it seems to me that it has dropped an earth, do you have any ideas where the earthing points are please.
When it stops raining will be a little more pleasent to investigate.
Again many thanks.
Cheers.
Geoff.
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Way2go
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Re: switches.

Post by Way2go »

Geoffrey Gould wrote:do you have any ideas where the earthing points are please.
Geoff.
Hi Geoff,

The PERMANENT earths on the drivers door switch which should have a BROWN socket are connected to pins 2 and 4 (2=Yellow wire, 4=Blue/Magenta wire) The OUTPUT earths are on pins 1 (Yellow/Green) and 5 (Yellow/Grey) respectively. ONE or OTHER (but not both at the same time) of these OUTPUT earths will change to +12v on operating the switch one way or the other. This change to +12 depends upon a PERMANENT +12v being connected to pin 3 (Blue) which is derived via the fuse and relay. (already checked?)

One of these OUTPUT earth lines has to be arriving at the passenger switch for one way operation you describe, check both are arriving. They go to pins 2 (Green) and 4 (Grey) respectively. Also check for +12v on either when operating the DRIVERS switch.

It is possible you have 2 faults, 1 with an earth and a second with the absence of +12v when switched through the drivers door.

I trust the car matches with the Haynes wiring (apart from them mixing up their LH & RH's) & let me know if anything is not clear or you need further info.
1991 BX19GTi Auto
Geoffrey Gould
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Post by Geoffrey Gould »

Thank you very much everyone, over the next week or so will have a go, everything is being held up a little by getting ready for an MOT and the b****y rain. But I will return and let you know what happens.
Once again ta it's bloody marvelous to have a forum like this with such a wealth of information and nice people.
Cheers.
Geoff.
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