side lights not working ?

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Black_Potato
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Post Mon Jul 08, 2013 10:57 pm

I have a problem with the side lights (the 2 small bulbs in the top of the lights, also known as parking lights) on the 320is. Its possible they have not worked for an age to be honest.

The normal dipped beam and full beam are fine, but when the headlight switch is pulled out to the 1st position they dont come on. A volt meter shows no current in either light socket & the bulbs are good. All the relays in the fuse box are good as are the relays.

Which leads me to think the switch is at fault but before I replace it is there anything else I can check ?
For instance is the absence of standard dash potentially have an impact? missing bulb or 3 that would sit behind the dash or in the glove box ?

Any tips/advise appreciated.

Cheers
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Brianmoooore
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Post Tue Jul 09, 2013 9:35 am

The left and right side light circuits are completely separate all the way from the power going into the switch, and that is unfused and shared by the number plate lights and panel lights.
If the tail lights are working, then the switch and fuses are all OK.
Did you check for power at the bulb holder or the plug and socket on the headlamp frame?
The short length of wire that goes from the plug and socket on the headlamp frame to the bulb holder is notoriously unreliable by BMW standards, and also ensure that the wire tails on the capless bulbs are lying where they should be.
Black_Potato
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Post Tue Jul 09, 2013 11:13 am

I've striped wiring both sides in the main loom and checked for +v and nothing. If I apply 12v at that point the lights work.

I can't actually recall if the rear lights work at the 1st click on the switch so I will check that tonight. Interior/plate lights dont exist anymore......
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Brianmoooore
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Post Tue Jul 09, 2013 1:29 pm

If it goes on the road at all it needs the speedo illumination bulb to pass a MOT test, and if it doesn't go on the road, why do you want front parking lights?
Black_Potato
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Post Tue Jul 09, 2013 1:57 pm

The plan is to put it on the road. The loom has only been was wired for track but it hasn't been cut back yet. The plan is to get it past an MOT and then remove the surplus loom.
The dash however will be a RaceTechnology Dash 2 though, this will illuminate on the same circuit if I don't hard wire it illuminated.
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Brianmoooore
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Post Tue Jul 09, 2013 2:03 pm

Number plate lights will be needed as well for that MOT test.
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Post Tue Jul 09, 2013 7:31 pm

So... Just checked. The rear lights come on at the 1st click.
Number plate lights are missing, but that's OK I can look at that after.

Re the front lights, do you know the route from them back to the switch? Is it direct or via various fuses etc?
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Brianmoooore
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Post Tue Jul 09, 2013 10:34 pm

The grey/white and grey/yellow wires that supply the corresponding front parking light and tail light are permanently connected together in the main body loom. There are no plugs, sockets, fuses, etc. between the front and rear lights on the same side, other than the bulb failure module for the tail lights on cars with a 'check' panel, but this would only be of relevance if the tail lights were out.
The wires from the front lights come back the LH inner wing and into the fusebox, but do not go directly to the relevant fuses. Instead, they go down the duct into the cabin, and are part of the body loom that goes across the dashboard area.
The actual joins are inside the loom just before where the branch to the centre console leaves the main loom.
Power must be reaching these joins, or the rear lights wouldn't work, and from there it's just the wires I've described to the front parking light plugs on the back of the headlamps.
At least, that's how BMW left it!
Black_Potato
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Post Tue Jul 09, 2013 11:30 pm

Thanks, very useful. I will follow them back when I get a chance, probably at the weekend.
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Black_Potato
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Post Sun Jul 14, 2013 11:33 am

Some progress, not quite as you explain it though.
Rear lights fine.
Y/Gry wire is fine and now with it connected the front parking light works.
W/Gry though is dead and after exposing the wire just behind the switch its dead there as well.
So maybe its time to change the switch?
Or I am considering a bodge of running both front parking lights of the Y/Gry wire, what do you think, much risk ?
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Brianmoooore
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Post Sun Jul 14, 2013 2:50 pm

Sounds like someone has already been bodging! If there's no power on the grey/white (not white/grey - that would be an ignition switched supply) where it leaves the switch, then the rear right tail lamp should not be lit!

Check for power on the grey/green wire at the switch. Should be live all of the time.
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Post Mon Jul 15, 2013 9:23 am

GW it is.

After I posted that I checked the rear number plate lights cabling (they dont exist at the moment) and the wiring is dead, both GW & GB dont have any voltage.

As before the rear side lights are good at 1st click though.

Will check in to the other wire you suggest as soon as I can.
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