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Discussion Starter · #1 ·
I'd been planning on rewiring my rear fog light switch for a while now and got around to sorting it this week. Using the aux switch is fairly straight forward. You just need to attach the live wire on the fog light to the live wire coming from the switch. It's the orange/black wire that's the live one.

MOT rules, however, require a "tell" to be present. I wanted to fit an LED to the aux switch whilst making it look as original as possible so I bought a spare switch on here so I could examine it and see what could be done.

As it turns out, it's possible to do it without even taking the switch apart!


The switch:





I bought the brightest 3mm led I could get from the local electronics shop. The grey diodes pull out and you can fit the LED though the hole they come out of, like so:





You need to wrap (I stripped some thin wire and used the casing) the legs of the LED to ensure there is no shorting as it is eventually wired separately. Test fit without wrapping:





I split the new live wire so that the power goes to both the LED and the rear fog light. The LED is grounded in the driver's footwell. Soldered up:





All put back together:





Not the best pictures, it's brighter in reality. And that's not light shining out the bottom, it's the reflection from the handbrake light.

Much better than the rocker switch that was there before!
 

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Nicely done!

Where is your actual fog light located? Have you used one of the existing bulb locations or added something new? I'm tempted to put a red led cluster into one of my reverse lights as the fog has to be a certain distance away from the brake lights
 

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Discussion Starter · #5 ·
You can see the bulb in there from some angles but it doesn't bother me and I'm usually quite anal about things being symetrical. Clear LEDs sound like a good idea but you'll have to make them fit.
 

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Guys my car has just failed an MOT for not having a rear foglight. I intend in using the O/S reverse light with a red bulb to make it work and an led on the switch above.
Could someone advise me with the wiring. The front LED.... earthed as close at possible. The rear bulb is already earthed...? But where are you picking up your positive feed from and you're running a wire from the front to the back of the car?
 

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Discussion Starter · #8 ·
Guys my car has just failed an MOT for not having a rear foglight. I intend in using the O/S reverse light with a red bulb to make it work and an led on the switch above.
Could someone advise me with the wiring. The front LED.... earthed as close at possible. The rear bulb is already earthed...? But where are you picking up your positive feed from and you're running a wire from the front to the back of the car?
Hi buddy , as it says in the first paragraph, it's the black and orange wire coming from the switch that's the live one. I'd still double check with a meter if you've got one but it shouldn't be any different.

I've earthed the LED onto a bolt behind the trim in the driver's foot-well.

The rear bulb is already earthed but it's worth checking its OK as when I first wired mine up it wouldn't work and it turned out to be that earth causing the problem.

The live wire needs to be routed through the car from front to back. Mine goes down through the dash behind the trim in the driver's foot-well, along the sill, behind the seat and through a grommet in the rear bulkhead, then behind the boot trim and down through another grommet behind the rear bumper and then to the bulb. It's completely hidden.
 

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Had a go, probably doing something silly wrong but i've connected the fog positive, led positive to the orange/black wire. When i press the fog light switch it works but the side lights come on too?

I assume everyone removed the orange lens from the rear light?
 

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Had a go, probably doing something silly wrong but i've connected the fog positive, led positive to the orange/black wire. When i press the fog light switch it works but the side lights come on too?

I assume everyone removed the orange lens from the rear light?
Ignore the orange lens i'm not thinking properly. Looked at the wrong light to what I wired in lol. Still having an issue with the side lights coming on when i press the switch. :runaway:
 

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Discussion Starter · #12 ·
Ignore the orange lens i'm not thinking properly. Looked at the wrong light to what I wired in lol. Still having an issue with the side lights coming on when i press the switch. :runaway:
Hmm, interesting. To be honest I've not checked to see if mine does that or not. I tested mine the way the MOT tester will as per this link:

UK MOT Information, Rear Foglights

Method of Inspection:

1.
With dipped head lamps and the ignition switched on, check:

a.
the presence, security and operation of the switch

b.
the presence and operation of the ***8216;tell-tale***8217;.

Note: Some ***8216;tell-tales***8217; may be in the form of a coloured tag on a switch.

2.
With the rear fog lamp(s) switched on check that a rear fog lamp:
a.
is securely fitted to the centre or offside of the vehicle

b.
is working

c.
is not obscured

d.
is in good condition
Note: An effective proprietary repair (e.g. lens repair tape etc.) must be assessed on its merits, considering security, colour, light output and durability.

e.
shows light of the correct colour

f.
is not adversely affected by the operation of any other lamp.
I think the logic is you wouldn't have the rear fog light on without your headlights on anyway.
 

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I'm doing mine this week. Thanks for the write up Andy616

Re fogs . I am former MOT tester and it must only operate in conjuction with sidelights and or headlights.

I adding a red lense like the aus cars seem to have. Might hate it but it has oem appeal lol.
 

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I've just done this mod, rear fog and tell tale light both working. But my side lights, tail lights and dash lights no longer work.

When I was doing it I forgot to insulate the legs on the led and blew the 15A for light fuse. Could I have blown another fuse? I've checked but they all seem in tact.

Any ideas guys?
 

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Reviving an old post but here goes!

I've been working on my mates R32. We reused the external wiring from the o/s fog to the grommet behind the Skyline panel. I cut the live and ground there and ran them forwards. I've used the ground in the footwell and spliced the live (green and white) into the black and orange for the aux lights switch. Not working though. The red bulb still works, as do the front fogs. :(

I feel like I'm being a complete derp and missing something, feel free to say so!

Thanks,
Aneesh
 

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Eh, I was being an imbecile and didn't ground it properly!

The led doesn't work though, I noticed that the thing wire wrapping the existing led to the switch came off, I'm assuming that's why it isn't working?
 

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Discussion Starter · #19 ·
Eh, I was being an imbecile and didn't ground it properly!

The led doesn't work though, I noticed that the thing wire wrapping the existing led to the switch came off, I'm assuming that's why it isn't working?
Sorry for the late reply, did you get this working in the end? I also had a grounding issue when I first did mine but that was with the factory earth at the back of the car.

I'm not sure why the LED wouldn't be working. The LED should be taking it's power from the same live wire as the fog light bulb, so if the light and switch are working it should be receiving power. A volt meter is very handy if you aren't already using one.
 
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