Interior lights

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Trise30rally
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Fri Nov 28, 2008 10:12 am

My interior lights work when i manually turn them on but will not turn on when i open the door.


I have read that the same door switch controlls the electric windows as well so you can open/close them when the door is open, well, guess what?? the windows don't work either but again, they work when i have the ignition on so there is something wrong with that switch circuit somewhere.....

Last night i removed the switch and much to my suprise it is a very simple switch that just seems to connect the single wire on the back to earth so i checked it for a circuit and it works fine.

Thats as far as i know to go, where shall i look next??
Trise30rally
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Sat Nov 29, 2008 9:52 am

Anyone?
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Brianmoooore
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Sat Nov 29, 2008 10:54 am

Should be two wires on seperate terminals on each switch!
Trise30rally
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Sun Nov 30, 2008 1:36 am

Yeah i realised that after i read a bit further but when i double checked there was only one wire.

Am i right in saying one is for the windows and one is for the lights? if so is it possible that the electric windows were retro fitted at a later date?

What else should i check for?
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Brianmoooore
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Sun Nov 30, 2008 9:58 am

Interior lights are an extremely simple circuit, if you don't have an interior lights delay module.
I've seen bent switch contacts inside an interior lamp, caused by hamfisted replacement of the bulb, and I've seen interior lights with the wires pushed on in the wrong places, but both of these would only affect that particular light.
The brown/purple wire you see connected in the lights is the same one that appears at the pin switches, with soldered joints, and a plug and socket right at the bottom of each B pillar.
Trise30rally
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Sun Nov 30, 2008 10:59 am

So does there have to be two wires at the switch for the lights to work?

Because at the moment the switch i have seems to be designed to short the single wire straight to earth.

I have already checked all of the terminals inside the lamp holder. :?
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Brianmoooore
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Sun Nov 30, 2008 10:11 pm

Only one wire, brown/purple needed at the pin switches for the interior lights to work.
Shorting the brown/purple to earth should turn the lights on.
Trise30rally
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Mon Dec 01, 2008 9:08 am

Right, thanks Brian.

Where do i look next if i do not get 12v at the light after the wire has been short to earth?
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Brianmoooore
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Mon Dec 01, 2008 9:21 am

If the lights work on manual, then you have 12 volts at the light!
Trise30rally
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Mon Dec 01, 2008 9:25 am

So its a switched earth?

Like the yanks?? :D
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Daz318is
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Wed Dec 03, 2008 5:34 pm

Hi
You should have 3 wires in your interior light, 1 perminent live, 1 perminent earth, and 1 switched earth which goes straight to the door switchs, so your door switch must be at fault, as they work when you switch manualy, check the 3 with the siple screw driver and wire tester, the 99p ones, hope this helps.

Darren
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