Help diagnosing dodgy window switch wiring

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Help diagnosing dodgy window switch wiring

Post by NebToast » Thu Aug 30, 2018 8:07 pm

Tried to fix my electric windows today. Nothing happened when you used the switches, and after looking at the Haynes (I think mine is factory original, could be dealer install though it's a 1992 GT2, the switches have LEDS in them) I identified the 30 amp fuse was blown. Replaced that, no change. So I took the door card off and the wiring was a bit of a mess on the driver side. Barrel crimp connectors all over the place with unhelpful wire colouring used. I traced them back and tried my best to connect back up the connections which had broken with some solder and shrink. Having fixed that the driver window would go up, but not down and nothing on the passenger.

Taking the button apart itself I got the window to go up and down by actuating the switch manually with a screwdriver, but only the driver side. It looks like my driver side switch is broken:
The up button doesn't click but it does work, the down button does click but it works intermittently. How do these switches work? Could I just super glue the top bit back together to make the mechanism work or should I get a new switch. If so does anyone know where to find one that's not super expensive? (My local breakers yard doesn't have a golf or roc sadly)

The problem of the other window not working is confusing because the wiring looks intact on the passenger side. When you click the up or down buttons the LED lights up like I assume it should but nothing happens. I'm confused with this one any help appreciated
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Re: Help diagnosing dodgy window switch wiring

Post by Jack92 » Tue Sep 11, 2018 6:20 am

Sounds like the passenger side is wired incorrectly. Personally I’d expect the led to either be on all the time or come on with the headlight switch, not when the widow button is pushed.

Get a multi meter and see what you are getting at the switch. Keeping the probes the same was round you should get around +12 up and -12 down (could be the other way depending on the way round the probes are)

As for the switch probably better just to replace it if you can find one but wouldn’t know where to start

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Re: Help diagnosing dodgy window switch wiring

Post by hanna.melbo » Tue Oct 16, 2018 8:57 pm

i have found that electrical contact cleaner and a fine sandpaper has worked for me in the past where there is grime on the connections adding resistance so the voltage cannot get through.
Other possibilities are:
No earth or negative from motor
Motor itself is faulty
check polarity of switch
I see this thread is quite old now so would be interesting to see how you got on?

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Re: Help diagnosing dodgy window switch wiring

Post by NebToast » Wed Jan 30, 2019 1:08 pm

I went ahead and bought a set of cheapo 5 pin switches off ebay and managed to get the driver side working with a multimeter and some trial and error. Then magically after taking the passenger doorcard off and putting it back on it started working too! I think the passenger window needed some jiggling to get going that's all.

The only trouble now is that the spade connectors I used stick too far into the door and the new switches don't sit flush with the door card. I need to fabricate some sort of holder for them, if anyone's got any tips I'd much appreciate.

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Re: Help diagnosing dodgy window switch wiring

Post by blakey » Wed Jan 30, 2019 8:34 pm

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