Hazard, rear defogger and folding roof switches not lighting

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Laith
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Post Wed Jul 17, 2013 10:27 pm

Do they have bulbs inside them that are replaceable or are they new switch jobbies?

Cheers
Last edited by Laith on Thu Jul 18, 2013 6:34 pm, edited 1 time in total.
TPS
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Post Wed Jul 17, 2013 10:30 pm

Does the Instrument cluster light up? Obviously none of these light up, without the lights on!
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Laith
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Post Wed Jul 17, 2013 10:34 pm

Yep, everything lights up. In fact I changed all the bulbs I could today, so the heating elements and OBC are fine. Just those three switches go into ninja mode at night. :?
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Post Wed Jul 17, 2013 10:40 pm

I come across a couple of times, where the brightness level was turned down, by turning the headlight switch, thinking there was a problem, when there wasn't!
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Laith
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Post Wed Jul 17, 2013 10:44 pm

Ok tried that, still doesn't work :(

I've got a funny feeling they have bulbs embedded in them? Or worse some wiring has gone somewhere.
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Post Wed Jul 17, 2013 10:51 pm

Not an expert, but I would say theres something more going on, that just the bulbs.
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Laith
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Post Wed Jul 17, 2013 10:59 pm

Ok tried that, still doesn't work :(

I've got a funny feeling they have bulbs embedded in them? Or worse some wiring has gone somewhere.
Grrrmachine
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Post Thu Jul 18, 2013 8:15 am

For some reason the rear demister only lights when activated - it doesn't glow with the other instrument lights.

Hazard switch should glow, but there are two types of bulb - one embedded, one removable.

No idea about the roof switch; I've never been in a cabby.

If you want to test the wiring, pull the hazard switch out of the dash, remove the switch from its plug, and put a multimeter or test bulb across pins 7 and 8 (grey/red wire and brown wire). With your interior lights on you should get a voltage there. If you do, your switch bulb is blown.

If you're handy with a soldering iron, you can get your demister switch to glow as well:

http://www.e30zone.net/e30zonewiki/inde ... dow_Switch
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Brianmoooore
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Post Thu Jul 18, 2013 9:29 am

The bulbs in the switches aren't intended to be replaceable, but they're not difficult to change if you want to. They are small wire ended 12 volt bulbs, similar in size to the OBC display ones, but with a lower light output.
CPC Farnel has suitable replacements, and the likes of RS Components probably has them as well.
I have no idea whether an electric roof switch is supposed to light up either, since I have only owned cabs. with manual roofs.
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Laith
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Post Thu Jul 18, 2013 10:58 am

Ok I might try prying them apart and having a look. Failing that, replacing them.

Cheers for the help
Grrrmachine
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Post Thu Jul 18, 2013 11:49 am

If you click the link I posted, it shows the two types of hazard switch. The one with the white circle in its base is a simple pull-out bulb.
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Laith
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Post Thu Jul 18, 2013 11:56 am

Nice one, I missed that link!
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Post Thu Jul 18, 2013 3:55 pm

I'm not 100% sure, but I don't think the electrical roof switches light up... TBH, it's not something I've looked out for, but will check next time
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Brianmoooore
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Post Thu Jul 18, 2013 6:33 pm

If there's a grey/red wire going to the switch base, then the chances are it's supposed to light up on the first and second positions of the light switch.
Lack of a wire doesn't prove that it doesn't light up, since it may be permanently lit when the ignition is on, like the window switches.