Temperamental window switches

[Bob Walker]

Hi Wuz
Have you seen this
https://www.youtube.com/watch?v=7RGvGz2P9mo
Bob

[Wuvz]

Originally Posted by SD1too

Hello Dave,

First of all thank you for your clear and comprehensive description of the fault in post no. 1.

I've checked the MGR manual and whereas the individual passenger door switches are hard wired to the BCU, all the driver's door switches communicate via a unidirectional dedicated data bus. This would appear to confirm that your fault most likely lies with the switch module or the wiring to the BCU.

Since all windows and the rear locking facility intermittently fail to operate, I would turn my attention to the contacts in the 6 pin connector (C0081) mounted to the rear of the module. Try switch cleaner and/or gently closing the female contacts slightly using a very fine tool.

1 = data stream to BCU
2 = switch illumination PWM signal
3 = 12v auxiliary supply from fuse 11
4 = Earth
5 = not used
6 = 12v battery

I hope that this helps!

Simon

Thanks Simon, that's very useful to know about the wiring setup.


I tried what you suggested with the contacts in the connector but unfortunately it hasn't made any difference. I also tried wiggling the plugs while operating the switches (with the switch pack out of the door obviously) in case there was a dodgy contact on one of the pins - that didn't work either.


Next thing to check I suppose is to find the other end of wire 1, where it connects to the BCU, and make sure the contacts there are all clean and tight. Do you have any idea which of the many wires going into the BCU is the data wire from the driver's door switches?

[Wuvz]

Originally Posted by Bob Walker

Hi Wuz
Have you seen this
https://www.youtube.com/watch?v=7RGvGz2P9mo
Bob

Yep - I watched that video (or one similar) before I took the switch pack apart - unfortunately that didn't resolve the non-working windows.

[SD1too]

Originally Posted by Wuvz

Next thing to check I suppose is to find the other end of wire 1, where it connects to the BCU ... Do you have any idea which of the many wires going into the BCU is the data wire from the driver's door switches?

This white/black wire goes via a 27 pin connector (C0336/C0459) in a rubber boot where the door loom enters the 'A' pillar to join the main harness. It's shown positioned just above the door check strap and is in a prime position for damage.

At the BCU it arrives on C0660 (centre connector, black, 54 pins) pin 33.

Taking great care check that the two 12v supplies are present on pins 3 & 6 at the door switchpack connector (using pin 4 as the earth for your meter if you can).

Simon

[dave lincs]

If you have checked the door multiplug from the body and it is OK I would send Trikey a message and ask him to put his t4 on it

[Wuvz]

Originally Posted by SD1too

This white/black wire goes via a 27 pin connector (C0336/C0459) in a rubber boot where the door loom enters the 'A' pillar to join the main harness. It's shown positioned just above the door check strap and is in a prime position for damage.

At the BCU it arrives on C0660 (centre connector, black, 54 pins) pin 33.

Taking great care check that the two 12v supplies are present on pins 3 & 6 at the door switchpack connector (using pin 4 as the earth for your meter if you can).

Simon

Thanks for that. (How does the "thank" function on this forum work? I can't see a button - am I missing something or does one need a certain number of posts before it appears?)


Looks like the wheelarch liner needs to come out to get at the multiplug, so that'll have to wait until I have a bit more time as I remember it being a right faff to get off last time I tried (the retaining screws are showing their age). Hopefully the multimeter will be enough to find out what's going wrong - if not then it may indeed be time for a T4 session...

[Yorkshire GOC]

Originally Posted by Wuvz

Thanks for that. (How does the "thank" function on this forum work? I can't see a button - am I missing something or does one need a certain number of posts before it appears?)


Looks like the wheelarch liner needs to come out to get at the multiplug, so that'll have to wait until I have a bit more time as I remember it being a right faff to get off last time I tried (the retaining screws are showing their age). Hopefully the multimeter will be enough to find out what's going wrong - if not then it may indeed be time for a T4 session...

You have to have made 10 or more posts to get the thanks option.

[daveo138]

Originally Posted by Wuvz

Thanks for that. (How does the "thank" function on this forum work? I can't see a button - am I missing something or does one need a certain number of posts before it appears?)
...

That confused me, for a while. It suddenly appeared (bottom right), so I figured it was to do with the number of posts.

[stevestrat]

Originally Posted by KWIL

Beware. Fibreglass pencils are VERY abrasive.

Don't scrub with it, brush whatever you are cleaning gently.