Yay!

 

Finally got around to doing the inner brake / fog light conversion. :dance:

 

Used relays on each light so that not only are the brake lights dual-function, but dummy loads (10ohm resistors) are switched in so you don't get the "LIGHTS" warning on the dash :nana2:

 

A well spent evening I think- time for a beer! :duffer:

 

Mark

 

[NB In my text and diagram below I originally made a mistake on the resistance required. I originally said 10 ohm when it should have been 6.8 ohm- bear that in mind when reading the responses!]

good job mate, im gonna convert one of my reverse lights to a fog by changing the bulb and wiring it up to a switch

Is there a write up for this? I'm gonna need to do that myself as I dont think I have a fog light... o_O

mrogers- mine had the reverse light conversion, but I got fed up of everyone saying "mate- one of your reversing lights isn't working", and not being able to see behind me!

 

W1NG- IIRC there's not so much a write-up but there's quite a bit of discussion about it. And there's a wiring diagram on Andy P's website here http://www.300zx.org.uk/brake-fog.htm

 

I based my set-up on that, but with the extra resistors which I don't think I've seen discussed on this site. (I think they're mentioned on the Z-Club site though).

 

If I can't find anything similar around I'll put a diagram together of wot I done...

 

Mark

 

Mark

mrogers- mine had the reverse light conversion, but I got fed up of everyone saying "mate- one of your reversing lights isn't working", and not being able to see behind me!

 

W1NG- IIRC there's not so much a write-up but there's quite a bit of discussion about it. And there's a wiring diagram on Andy P's website here http://www.300zx.org.uk/brake-fog.htm

 

I based my set-up on that, but with the extra resistors which I don't think I've seen discussed on this site. (I think they're mentioned on the Z-Club site though).

 

If I can't find anything similar around I'll put a diagram together of wot I done...

 

Mark

 

Mark

 

A diagram would be great. I've done the conversion but the brake warning light is a pain. I only used a single relay IIRC - not sure if that will change things.

 

Cheers

 

 

David

Hmm- there was an echo in my message!

 

silverfox- it depends on the relay and whether you're switching both inner lights or just one. I used double-pole, double-changeover relays. And they're normal "consumer" relays rather than automotive ones- I couldn't find auto ones with the right contact setup.

 

Mark

W1NG- IIRC there's not so much a write-up but there's quite a bit of discussion about it. And there's a wiring diagram on Andy P's website here http://www.300zx.org.uk/brake-fog.htm

Ah, right, those diagrams. I really hate reading them... I thought I had enough of them in Computing! >_

 

I'll have a go at it but if all fails I could always use my Raybrig R1300 remote control front fog lights that I took off of my Civic for the rear fog lights. :dance:

Mine had the inners wired up as fogs when i got it but i wanted to get all 5 brake lights at the back working together, so i rewired it back to stock then bought mtself one of those hi level brake lights that attaches on a bracket so you can adjust the angle, i then attached it to the inside of the rear bumper. So at mot time, or if i manage to find some fog i just fold it down, once its over i just fold it back up under the bumper out of sight again.

 

Also a good thing to remember when wiring in fogs is you must have some sort of illumination or indicator in the cockpit to show when its in use, or it willst fail the mot.

mine have the fog lights wired in so if they r of use to anyone?

Ready made Zed fogs?! That's no fun! :D

Here are the wiring diagrams for my arrangement.

 

Firstly, this is what you start with:

 

 

The "Stop and Tail Lamp sensor" is the little black box mounted on the side of the tail lamps (driver's side).

 

The rear lamp mounting bracket, which passes vertically between the 2 brake lights, is very handy for mounting the relay.

 

I screwed the dummy-load resistors into the body, but watch out if you do this as I almost chose to mount them above the bumper-line, so the screws would have gone all the way through! :slap:

 

I ran new earth wires to the earthing point screwed into the body right in the middle at the back.

 

Note I've only shown one side- obviously you repeat it on the other side if having 2 fog lamps. I power the 2 relays in parallel from the fog switch, but feed power to the 2nd fog lamp from the other side-light feed to the lamp sensor (does that make sense?!).

 

The 6.8 Ohm resistor has to dissipate 21W, so make sure you get an appropriate component.

 

I'm a cautious person who doesn't want to risk burning anything out, so I'd recommend using something which can handle the worst case (i.e. 21W continuous). As 6.8 ohm resistors are hard to come by at 25W (the nearest power rating), you can either go for:

• the right resistance at a higher rating (100W, expensive!)
  
• a combination of resistors in parallel (10 ohm 15W + 22 ohm 7W)
  or
  
• closest resistance at the right rating (8.2 ohm 25W)
  

I'll leave that decision up to you! (NB I got my sums wrong to start with and put in a 10 ohm only- this seems to work in warm weather but not cold! So the 8.2 ohm *might* just be ok. I'll update this text as and when I find things out!)

 

Also be aware that the power rating of some resistors is dependent on them being attached to a heat-sink- you may have to double the power rating if they won't be attached to a metal body.

 

Mark

Is it OK if I add those pics to my site ?

Sure thing Andy. :cool:

 

Mark

Ooo I forgot to say- the 10 Ohm resistor has to dissipate 14W, so make sure you get an appropriate component.

 

Now in general you'll probably be ok with something rated lower (say 5W) but I'm a cautious person who doesn't want to risk burning anything out, so I'd recommend using something which can handle the worst case (i.e. 15W continuous).

 

Also be aware that often the power rating of resistors is dependent on them being attached to a heat-sink. So if you use heat-sink gunk attached to metal bodywork, a 15W resistor would be ok. Otherwise you'll have to use something rated at about 30W.

Here are the wiring diagrams for my arrangement.

 

Firstly, this is what you start with:

 

And this is how you end up:

 

The "Stop and Tail Lamp sensor" is the little black box mounted on the side of the tail lamps (driver's side).

 

The rear lamp mounting bracket, which passes vertically between the 2 brake lights, is very handy for mounting the relay.

 

I screwed the dummy-load resistors into the body, but watch out if you do this as I almost chose to mount them above the bumper-line, so the screws would have gone all the way through! :slap:

 

I ran new earth wires to the earthing point screwed into the body right in the middle at the back.

 

Note I've only shown one side- obviously you repeat it on the other side if having 2 fog lamps. I power the 2 relays in parallel from the fog switch, but feed power to the 2nd fog lamp from the other side-light feed to the lamp sensor (does that make sense?!).

 

The 10 Ohm resistor has to dissipate 14W, so make sure you get an appropriate component.

 

Now in general you'll probably be ok with something rated lower (say 5W) but I'm a cautious person who doesn't want to risk burning anything out, so I'd recommend using something which can handle the worst case (i.e. 15W continuous).

 

Also be aware that often the power rating of resistors is dependent on them being attached to a heat-sink. So if you use heat-sink gunk attached to metal bodywork, a 15W resistor would be ok. Otherwise you'll have to use something rated at about 30W.

 

Mark

Dont wat to appear a DINNY but how many of these resistors do you need??????

Chaz :headvswal

2- 1 for each side :)

 

I tried drawing a diagram for both inner lamps and it was just a nightmare! So I hoped that people would get the idea from this, and just duplicate it.

 

If you need any other help let me know! :D

 

Mark

2- 1 for each side :)

 

I tried drawing a diagram for both inner lamps and it was just a nightmare! So I hoped that people would get the idea from this, and just duplicate it.

 

If you need any other help let me know! :D

 

Mark

Cheers mate,I actually did'nt do the conversion, although I did the preparation,ie wiring from front to rear and utilised the spare empty switch position ,the one beside the lekky mirror switch.Got a spare switch block from Andyz and used the mirror switch out of that for the foglight power on switch

Had to do a little soldering inside the switch,though. All very neat and looks like it's meant to be there.Unfortunately when I had the job done we did'nt have the resistors to hand Have now got a pair of 10 Ohm 25w Just have to know where they go!!!!!!!!!!!!!!!

Chaz

Cheers mate,I actually did'nt do the conversion, although I did the preparation,ie wiring from front to rear and utilised the spare empty switch position ,the one beside the lekky mirror switch.Got a spare switch block from Andyz and used the mirror switch out of that for the foglight power on switch

Had to do a little soldering inside the switch,though. All very neat and looks like it's meant to be there.Unfortunately when I had the job done we did'nt have the resistors to hand Have now got a pair of 10 Ohm 25w Just have to know where they go!!!!!!!!!!!!!!!

Chaz

 

PS NNot sure if anyone on the forum has done the above the same???????

Got a spare switch block from Andyz and used the mirror switch out of that for the foglight power on switch

 

IIRC doesn't the rear fog switch have to be a tell-tale one i.e light up or illuminate a bulb or something???

IIRC doesn't the rear fog switch have to be a tell-tale one i.e light up or illuminate a bulb or something???

Yes there is a separate telltale light fitted to the dash in pretty green

 

Chaz

Sounds like an elegant installation! :cool:

 

Mark

:cool: