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Fog lights not working...

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DMC63
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Fog lights not working...

Post by DMC63 » Fri Aug 03, 2018 8:46 am

Following on from buying LED fog light bulbs the saga continues...
Background: 2003 2.5
Cars fogs working with one bulb blown. The bulbs kept blowing only on one side. Can't recall whether it was the same side at a time, never both at once.
Car goes in to BMW for new starter motor and to my knowledge with one fog bulb blown.
BMW tell me that the bulb holder needs replacing £340 HAHA! :rofl: Of course it has and at that price best do both....NOT!!
I tell them it's a blown bulb, they (supposedly) leave it alone, fix the starter motor and give me the car back.
I fit the new LED's.
Sequence.
1. Turn lights to side lights.
2. Press fog button.....Nothing, no yellow fog indicator light on dash...
3.Turn the lights to dipped beam
4. Press fog button... yellow fog indicator light shows on dash but both fogs are not on.
5. Replace old bulbs, one is working.
6. Turn lights to side lights.
7. Press fog button.....Nothing, no yellow fog indicator light on dash...
8.Turn the lights to dipped beam
9. Press fog button... yellow fog indicator light shows on dash but both fogs are not on.

Does anyone have any suggestions on where to start to get the fogs working again...

The fuse is working.

If the fog indicator light is on the dash with dipped beam and the fogs not on, what could that be?

UPDATE!
I've been reading up on this and I've checked for a click (relay) when I press the front fog button on the dash.... :tumbleweed: No click..
When I press the rear fog I get the little click.
Even when on dipped beam and I press the button there's no click but the yellow light comes on...
So to recap thus far...the yellow dash light not coming on with sidelights position and IS coming on with dipped beam position but there are NO relay clicks either position and no lights at all.
Last edited by DMC63 on Sat Aug 04, 2018 8:27 am, edited 2 times in total.
BMW Z4 2003 2.5i and lots of bits and pieces - 2016 - 2020 Sold

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DMC63
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Fog lights not working...

Post by DMC63 » Fri Aug 03, 2018 10:29 am

UPDATE OF THE UPDATE :?

This isn't a good sign...I'm answering my own thread :cry:
Ok, I've managed to get this far...
I've checked the fuse. It's ok.
I've got the front fogs to work but only when the rear fogs are switched on. Front and rear fog lights work together in sidelights and dipped beam positions.
If I switch the rear fogs off the fronts don't work :|
And take me back to the scenario I've outlined above...
Could this be a programming problem?

Prior to this scenario the front and rear fogs worked independently on both dipped and sidelight settings.
BMW Z4 2003 2.5i and lots of bits and pieces - 2016 - 2020 Sold

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DMC63
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Fog lights not working...

Post by DMC63 » Sat Aug 04, 2018 8:29 am

I'm surprised there's no one here who can work out this conundrum :?
BMW Z4 2003 2.5i and lots of bits and pieces - 2016 - 2020 Sold

Scooba_Steve
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Fog lights not working...

Post by Scooba_Steve » Mon Aug 06, 2018 10:19 pm

Seems odd that one side is blowing and the fuse is ok.

I thought the light switch centre self tested, but it sounds like the problem may be there - I can't imagine the garage causing the issue or programming it. I'm not sure what the fog options are though.

There should only be a relay on the front fogs, the rear is powered direct from the LCZ.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

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DMC63
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Fog lights not working...

Post by DMC63 » Tue Aug 07, 2018 10:54 am

Scooba_Steve wrote: Mon Aug 06, 2018 10:19 pm Seems odd that one side is blowing and the fuse is ok.

I thought the light switch centre self tested, but it sounds like the problem may be there - I can't imagine the garage causing the issue or programming it. I'm not sure what the fog options are though.

There should only be a relay on the front fogs, the rear is powered direct from the LCZ.
Thanks Steve. I'll have to look into this further.
BMW Z4 2003 2.5i and lots of bits and pieces - 2016 - 2020 Sold

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Fog lights not working...

Post by Scooba_Steve » Tue Aug 07, 2018 11:09 am

I'm not sure what effect disconnecting the LCM and turning ignition on will have, but one method to test the fog circuit would be to apply 12 V to the front fog LCM output directly. If they then worked as expected that would point to the LCM being faulty.
INPA has the ability to activate individual circuits, that would be my preference to try first, not sure if Carly can do that.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

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Fog lights not working...

Post by DMC63 » Thu Aug 09, 2018 9:01 am

Scooba_Steve wrote: Tue Aug 07, 2018 11:09 am I'm not sure what effect disconnecting the LCM and turning ignition on will have, but one method to test the fog circuit would be to apply 12 V to the front fog LCM output directly. If they then worked as expected that would point to the LCM being faulty.
INPA has the ability to activate individual circuits, that would be my preference to try first, not sure if Carly can do that.
Thanks Steve. My neighbor is AA I'll run this past him, he's got a diagnostics set-up. The fogs work but not without switching the rears on first.
BMW Z4 2003 2.5i and lots of bits and pieces - 2016 - 2020 Sold

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