Helping A Friend How To Make Taillights Work Like Taillights

[scithe93]

hey guys im helping a friend out with converting there r31 skyline hotplates to leds and was wondering how I would get the lights to come on at a dimmed brightness as taillights and full brightness as brake lights. ive done heaps of research on it as I was going to do this when I had my r31 but am unsure how the led rings would work as taillights when there are only 2 wires off the led?

is this already setup in the taillight harness and all il have to do is wire the lights into the existing harness?

will I just be able to wire the leds into a plug and plug them into the existing taillight harness? and if I do this will they still work?

I have the hotplates and the led rings im going to use already but cant figure out how to make them work as taillights, I spoke to my local auto elec but he didn't understand what I was trying to explain so I hope you guys can.

also will I be able to wire both individual led rings into one plug to plug into the existing harness in boot of car?

as you can tell I know how to do most of the work but I cant figure out the electrical side with wiring, also can I just use the existing plug on the hotplates and will I need a relay of any sort?

hope you can help me figure this out as if it all works out I wanna start doing it as a at home business due to the fact there is no off the shelf aftermarket led taillights.

cheers in advance guys

[Duncan]

I am 99% sure you can't do what you want with those lights.

It is very uncommon for LEDs to be able to be dimmed, some expensive 240v ones allow for this by adding a resister but cheapies will either be on or off, not dimmable.

[r31slpr]

Got the specs on the lights?

A micro controller and PWM (pulse width modulation) can do what you want. But probably a bit too complicated for what your after

[scithe93]

the lights are 39 smd, chip type 1210, voltage dc12v

if I cant doit the way I was hoping would it be possible to wire the outter ring as the taillight and inner ring as the brake light? there 2 separate leds with separate wiring so this should be possible am I correct?

am I going to be able to wire the leds into the existing taillight loom in the boot by using the original plug on the taillights?

were can I buy a micro controller and pwm and how exactly do they work? all were trying to do is convert the standard taillight to leds by changing the internals.

[r31slpr]

By specs I mean do you have a link to the unit, it will be easier to help then.

Sorry I read your first post as only having one ring that you wanted to use for both park and brake. If you have two rings it will be easy as, you will probably need a resistor for the park lights. Need more info on the lights to figure it out though.

Yep should be able to do that, provided everything else is sorted first.

Disregard what I said about micro controllers and pwm if you have two rings per light

[scithe93]

oh sorry, I cant find the link atm but il have a proper look tonight and post the link up. so would it be easier to just have the outter ring light up as the taillight and then the inner ring only come on as the brake light?

and the original post I wanted both ring to light up as taillights and get brighter when I brake but if that's not possible il have to go a different path so il use the outter light as the taillight and the inner light as the brake light. will I be able to wire both outter and inner lights into the old plug or will the brake light need to be wired seperatly so it only comes on when I apply the brake?

Edited July 24, 2014 by scithe93

[scithe93]

ive drawn up what the design I wanted is and what the design im gunna settle for is on paint on my laptop but cant figure out how to upload them to this post. if someone knows how I can put the pictures up to give you a rough idea of what I was trying to do

[r31slpr]

It's entirely possible haha sorry a bit off my game today.

To upload images, host it using something like photobucket then copy the img tags into your post.

If I've got it right here's an easy way to use the same light as stop/tail. (the single led represents all of yours)

Just need the specs on the lights to figure out R1 and R2

[niZmO_Man]

You'll need to think up a voltage divider circuit for the park lights.

Or... Two circuits connecting the LEDs (depending on how you want the lights arranged), one circuit connecting to park and the other to the brake wiring. Not sure what voltages are outputted (you can easily measure those), but a crude way of wiring them up... pretty much what r31slpr posted.

After some diodes and resistors, the lights should get e.g. 5V for park and 12V for brake.

[scithe93]

sweet as cheers guys when it comes to electricals im not einstien lol only doing it to help a mate out coz I know how to pull the 31 lights apart and reseal then perfectly. I put a foot up his arse when im over there on the weekend and get the specs and were he bought the leds from anf get back to ya's