No light on bulb

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Benzon
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Post Fri Oct 30, 2015 4:38 pm

Hey, im trying to fix my dash bord astray light 2 bulbs, and and the 2 bulbs around the heater. The ting is, there is two wires, and there is 12v on both of them, so some how the ground i missing, but Maybe anyone else have tried this? Why are there 12v on both wires? The bulb is New, so they are fine.. Any ideas? ? OBS;: everyting else works, switch light on sunroof, and switch for Windows light works fine, blink kamp etc is light. Is only dash bord astray light and the 2 bulb around the heater not working.
E30 320i 1988
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Brianmoooore
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Post Fri Oct 30, 2015 6:45 pm

The 'ground' for these bulbs is a brown/white wire, which is earthed via a rotary dimmer, which is part of the main lighting switch.
You'll probably find that the dimmer has burnt out, usually as a result of getting a full 12 volts applied across it.
Sunroof switch light, window switch lights and light for the fog and main lighting switch are switched on with the ignition, and not part of the sidelight circuit.
Blink kamp????
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Benzon
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Post Sat Oct 31, 2015 12:27 am

Blink lamp* left and right u know. But thanks for answer. Ill try to look at it
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Brianmoooore
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Post Sat Oct 31, 2015 9:56 am

Benzon wrote:Blink lamp* left and right u know.
Ah, right. Again, nothing to do with the panel illumination.
Just read the OP again, and note that you don't mention the illumination for the instrument cluster. These two bulbs should be out as well if the dimmer is at fault.
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Benzon
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Post Sat Oct 31, 2015 12:17 pm

So I Thing lll just buy a New light switch, right?
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Brianmoooore
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Post Sat Oct 31, 2015 1:51 pm

Benzon wrote:So I Thing lll just buy a New light switch, right?

Be a good idea to check first!
Extract the bulb holder from under the rear ashtray (easiest to get at), and use a piece of wire to connect the brown/white wire to a good body earth, such as a hand brake lever bolt or the sides of the cigarette lighter socket.
This should make all the bulbs that don't work light at full brightness when you pull the main lighting switch knob out to the first position.
All the above assumes that you've tried rotating the knob fully clockwise? (You wouldn't be the first!)
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Benzon
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Post Sat Oct 31, 2015 3:52 pm

Right, but when i pull the light switch knob out, the parking light does work. But ill try to do what u said, ill make make a wire (ground) and Connect to the brown/white wire and see if it works :-)