Intermittent Drivers Window Switchpack Fault

[TomTheTyke]

Hi all,

As above, have developed an intermittently faulty drivers window switch pack.

Keeps occasionally needing multiple presses to operate any window, seems to temporarily fix itself sometimes, others it takes a minute of pressing to get a response.

I’ve had the switchpack apart, contact cleaner to the PCB and cleaned the membrane, but no difference. I’ve also sprayed contact cleaner on the connectors.

I did notice the mirror selector led was faint / flickering. Could this be a bad earth? Where does it earth?

Which fuses (which fuse box) should I check?

I want to exhaust other options before buying a replacement switch pack.

Thanks in advance, any help much appreciated.

[SD1too]

Originally Posted by TomTheTyke

Keeps occasionally needing multiple presses to operate any window, seems to temporarily fix itself sometimes, others it takes a minute of pressing to get a response.

Apply silicone spray to the glass channels in the door frame Tom. This worked on Lida's car when she had the symptoms you've described.

Simon

[TomTheTyke]

Originally Posted by SD1too

Apply silicone spray to the glass channels in the door frame Tom. This worked on Lida's car when she had the symptoms you've described.

Simon

Thanks Simon. I’ve given it a try.
Am I missing something obvious though as I’m not sure on the logic of this? It seemed more electrical than mechanical, given that when the switch isn’t working it won’t operate any of the 4 windows.

Is the switchpack throwing a wobbly because the glass is sticking?

[SD1too]

Originally Posted by TomTheTyke

Thanks Simon. I’ve given it a try.

Did you treat all four doors and did it work?

Simon

[TomTheTyke]

Unfortunately this made no difference.

I press the one touch down and it goes half way down then I hear the relay click and the window stops. Also happens passenger door using the passenger door switch.

I have given all the a pillar earths a blast of contact cleaner but they seem tight.

BCU?

[SD1too]

Originally Posted by TomTheTyke

I did notice the mirror selector led was faint / flickering. Could this be a bad earth? Where does it earth?

I've looked at the wiring diagrams for you Tom and the mirror switching circuit shares an earth with the front driver's side window switch (DDM: Driver's Door Module).

The earth is C0706 which is located behind the carpet at the base of the RH 'A' pillar. There are several earthing points here; you need the lowermost, nearest the floorpan. It will have a total of eight black wires attached to an eyelet.

Simon

[TomTheTyke]

Thanks Simon. I found that earth, though as you say there are a few down there, nothing felt at all loose and I have them all a good blast of contact cleaner but it’s made no difference.

I’ve also gone back and given everything a more thorough dose of silicone spray.

But as I said earlier surely all 4 windows experiencing issues suggests electrical rather than mechanical. It also did affect the switches on the other doors.

This leads me to query the BCU. The Pektron units as in my TF fail for fun and have spawned several mail order businesses specialising is soldering in new relays - I’ve not read much about failures here. I can definitely hear the relay clicking off when the window stops even though the switch is pressed, though again that could be a signal issue.

Any suggests as to what order to try things?

[vitesse]

If you have Toaf, or some kind soul locally has, you can activate each of the windows using the programme which will prove the BCU is working (or not).

Anyone locally who you could borrow a master switchback from, alternatively can't cost that much at a UK breaker's.

Good luck

[SD1too]

Originally Posted by TomTheTyke

I found that earth, though as you say there are a few down there, nothing felt at all loose and I have them all a good blast of contact cleaner but it’s made no difference.

Hi Tom,

You've said previously that you suspect this earthing point. What you need to do is to remove the screw and check that all the eyelets are bright and shiny as well as the contact surface on the body. If all this is in order then turn to the power supply feeding the flickering mirror selector LED.

Originally Posted by TomTheTyke

I can definitely hear the relay clicking off when the window stops even though the switch is pressed ...

Which window? Just the driver's side or all of them? If we're to narrow this down we need detail!

Simon

[TomTheTyke]

Update. I found the earth, it was the lowermost at the RH side tho I only counted 7 wires to it. I’ve cleaned it up.

On the drive everything worked fine.

This morning on the way to work, back to the flickering light and the operation of the windows worse than ever. The light flickers and the relay clicks, whichever window I am trying to lower.

I have ordered a replacement switch pack, from a breakers just to rule that out.