Let’s say you were to add led strip lights to the sides of your vehicles because you wanted them to turn on when you put on your turn signals. It may seem like a mammoth task, but it is actually pretty simple, here’s how you’d do it:

  • You would need 2 diodes and 1 resistor on each side.
  • The parking light wire needs to run through the diode, then through the resistor, and to the positive of  your flexible led strip.
  • Run the “turn signal” wire through the other diode to the positive of your led strip.
  • Connect the negative of the led strip to the ground wire.


FORUM THREAD


Tonywp75

Joined: Dec 21 2007
Posts: 3
Post Fri Dec 21, 2007 9:46 pm

Hey all,

Just join the forum, ben lurking around for a few months. I just installed a few CCT and some LED strips…everything turn out AWSOME. Thanks to the Great info here.

I was planing on wiring LED strips to the side skirt of my body Kit. I drive a 05 Acura TL and going to install the Aspec kit. I want to wire the LED strips to the turn signal, but there are 3 wires for the turn signal light. I think they are ground, signal, and parking light.

I want my LED strips to turn on when I put on my turning light and parking light. Is there a way to do that???????????

I havent play around with wire it yet, maybe when it get a little warmer. I was thinking just to use a tap a wire to one of the wire and the ground and that might work. I have to play around with it.

Anyone know or have any idea.?

TeDy

Joined: Jun 07 2007
Posts: 218
Post Fri Dec 21, 2007 9:55 pm

Should be pretty simple. Have the parking wire and the signal wire hooked up to the positive part of the LED strip, and put a diode on each one so it doesn’t feed back.
mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Fri Dec 21, 2007 11:25 pm

Yeah, it’s pretty simple to do….

Each side will need 2 diodes and a resistor. You will run the parking light wire through a diode, then a resistor, and to the positive of the strip. The “Signal” wire will run through a diode to the positive of the strip. Then the negative of the strip to the ground wire.

This will turn the strip on with your running lights, but they won’t be at full brightness. They will also flash with your turn signals at full brightness.

I’ll draw up a diagram tomorrow if you need help…

And welcome to Oz

oh, and “lurking” what do we have a stalker here? icon_lol.gif

Chris

Joined: Sep 27 2004
Posts: 2395
Location: NY
Post Sat Dec 22, 2007 12:53 am

MX you are a genius.

I would love to see a diagram for this along with a link to the type of diodes that are needed.

I’m looking to do the same thing, so can you help me out as well?

Thanks man!

TeDy

Joined: Jun 07 2007
Posts: 218
Post Sat Dec 22, 2007 4:05 am

icon_rolleyes.gif icon_neutral.gif
Radioflyer

Joined: Sep 25 2007
Posts: 1563
Post Sat Dec 22, 2007 11:26 am

For cars that use the DRLs as turn signals, you can tap into the tirn signal wire under the dash for a “turn signal only” connection.
Tonywp75

Joined: Dec 21 2007
Posts: 3
Post Sat Dec 22, 2007 1:36 pm

mx107marlin wrote:
Yeah, it’s pretty simple to do….

Each side will need 2 diodes and a resistor. You will run the parking light wire through a diode, then a resistor, and to the positive of the strip. The “Signal” wire will run through a diode to the positive of the strip. Then the negative of the strip to the ground wire.

This will turn the strip on with your running lights, but they won’t be at full brightness. They will also flash with your turn signals at full brightness.

I’ll draw up a diagram tomorrow if you need help…

And welcome to Oz

oh, and “lurking” what do we have a stalker here? icon_lol.gif

Wow..thanks for all the help everyone. A Diagram would be Great!

I never used any diode or resistor before..Im a noobie as you can see. But with all the help here Im sure I will get the hang ot it.

Thanks for the Warm Welcome!! Oznuim Rocks!!! mj.gif

TeDy

Joined: Jun 07 2007
Posts: 218
Post Sat Dec 22, 2007 2:20 pm

MX I’m going to squish your bug.
mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Sat Dec 22, 2007 5:46 pm

Tonywp75 wrote:
Wow..thanks for all the help everyone. A Diagram would be Great!

I never used any diode or resistor before..Im a noobie as you can see. But with all the help here Im sure I will get the hang ot it.

Thanks for the Warm Welcome!! Oznuim Rocks!!! mj.gif

No problem…. do you know how to solder? That’s gonna be the first step…

If you don’t know how to do it, or don’t want to buy an iron, I’ll be more than happy to do the simple soldering for you. If you pay for shipping and parts I’ll assemble this for you…

I’ll draw up a diagram as soon as I can, but right now I’m installing Adobe CS3 Master Suite and my computer is severely bogged down…. I’m lucky to be able to type this…

As soon as my computer gets up and running smoothly, I’ll draw it out.

TeDy wrote:
MX I’m going to squish your bug.

You wouldn’t be the first to try… I’m not responsible for getting you a new monitor though if you break your’s trying to kill that thing icon_razz.gif icon_lol.gif

PwrRngr

Joined: Jul 19 2007
Posts: 4407
Post Sat Dec 22, 2007 7:52 pm

Tonywp75 wrote:
Wow..thanks for all the help everyone. A Diagram would be Great!

I never used any diode or resistor before..Im a noobie as you can see. But with all the help here Im sure I will get the hang ot it.

Thanks for the Warm Welcome!! Oznuim Rocks!!! mj.gif

Like MX said, learn to solder first. It’s not hard while working with big items that go w/ lighting (avoid surface mount until you’re better). Resistors don’t have a positive and negative terminal so it doesn’t matter which way they’re wired in the circuit. Diodes on the other hand do and it’s very important those are set up correctly.

Tonywp75

Joined: Dec 21 2007
Posts: 3
Post Sat Dec 22, 2007 8:18 pm

Funny you guys mentioned soldering, I was about to get into that. I held my first soldering iron last week after a computer fan wire broke off the circuit board. I was bored working the night shift and got some solder and a solder iron from a co-worker desk. His Iron sucked, the tip wasnt hot enough to melt the solder.

I was looking online and was thinking about buying a cold heat soldering iron. What do you guys use any recommendation?

Where can I buy resistors and diodes at a good price? Any other supplies I might need?

I want to have everything ready, so I dont have to run around or wait..when i decide to do this mod.

mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Sat Dec 22, 2007 8:45 pm

Alright…. I got you a diagram…

It looks complex for someone without much experience…. keep in mind you only need to be concerned with the parts within the dotted areas.

The colors are as follows:

Blue – Running lights
Green/Yellow – Turn Signal (Right/Left)
Black – Ground

I don’t know what the resistor value should be right now though… I don’t know enough about the LED strips. What length of strips do you want to use for each side.

EDIT: Just saw your post. Downside to the cold heat irons (I work at Radio Shack, we sell a bunch of them) is that the tips are made of graphite, which is very brittle. If you touch it the wrong way, the tip will break. If you have a Radio Shack near you, get either the 15/30 watt switchable iron, or one of the 45 watt irons. Get you some solder, and one of the cheap tool sets. That will make life easier.

Oh, and if you have a Radio Shack near you…. you can get most of your diodes, resistors, and other smaller things there… more complex IC’s and stuff like that will require ordering online.

PwrRngr

Joined: Jul 19 2007
Posts: 4407
Post Sun Dec 23, 2007 7:51 am

I personally don’t like cold heat soldering irons. I always seem to get a bad connection that doesn’t melt the solder through the whole wire.
bshupe

Joined: Dec 27 2007
Posts: 7
Post Fri Dec 28, 2007 5:18 pm

I just bought some of the 2.4″ strips in amber to make side mirror signals. With what Im seeing here I would like apply this wiring to them and make them into side markers AND turn signals.

What size resister would be proper for the small strips? Is there a specific diode that would be best? Also, would you recomend using a project box with a little bread board in it and then just patch into the wiring harness or you just put the diode and resistor on the strip under heat shrink etc?

Thanks.

mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Fri Dec 28, 2007 7:05 pm

I personally would put the diode and resistor under heat shrink in line with the wire like in the diagram.

Which strips did you buy… I don’t see the Flexible LED Strips in Amber, could you put a link in here to the specific product you bought?

bshupe

Joined: Dec 27 2007
Posts: 7
Post Mon Dec 31, 2007 10:53 am

mx107marlin wrote:
I personally would put the diode and resistor under heat shrink in line with the wire like in the diagram.

Which strips did you buy… I don’t see the Flexible LED Strips in Amber, could you put a link in here to the specific product you bought?

Thanks for the input, I think I agree for simplicities sake. Part of my problem is that this will be my first LED install and I dont really know how physically large the diode will be and therfore how much space I will need for it. Since I am installing them on the side mirror it wont be easy to pull them out if some repair is required. I am already a little shy about installing them as I have read in these forums of people having the lights burn out in the flex strips. This could be due to improper wiring but none the less they dont seem to have the life that I would hope for in an LED.

My mistake on the color. They are listed on the main flex strip page as Orange. I refer to it as amber in an automotive contex and, now that I have them (lighting fast shipping, thanks Oznium) they are within the color range of amber so I feel OK referring to them that way.

Anyone have the specs for the resistor for the 2.4″ strips?

Thanks again.

mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Wed Jan 02, 2008 8:23 pm

If you are using the 2.4″ Orange (or any color for that matter) Flexible LED strips, the resistors that you need in the diagram above should be approx 75-ohm, 1watt

This should, if I’m right, drop the voltage to 6V and approx half the brightness… this really is something that you should benchtest to see what you like…

To bench test the size of the resistor that you would need… buy a pack of several assorted sizes (they aren’t expensive) and hook up your LED strip to a 12V battery (I highly recommend a “N” size battery and a “N” size battery holder from Radio Shack, the will bench test anything that requires less than 500mA to operate) Put the resistor in series somewhere (positive or negative) and see how much the light dims, if you think it’s dim enough to be a running light, use that resistor, if you think its too bright, use a bigger resistor, if you think it’s too dark, use a smaller one. Repeat until you find a brightness that you like.

Acey

Joined: Sep 01 2007
Posts: 117
Location: Calgary
Post Mon Jan 21, 2008 10:55 pm

Alright, I’m doing this in my ’01 Z24 Cavalier, I just bought the strips. When the turn signal is activated, the strip will flash from full brightness to resistor brightness and back? How exactly do the diodes function? The diodes on the running lamp wires stop current to allow full brightness with the signal?
Black DX

Joined: Oct 16 2007
Posts: 1007
Post Tue Jan 22, 2008 5:13 pm

The diodes prevent the 12+ from chasing back up the line and powering the other things connected to it when not wanted (so like when you flash your turn signal it doesn’t strobe your running lights as well), the diode on the flash input line dose the same thing but it prevents the turn lights from being turned constant on with the running lights…

If you have it wired up like the picture with the diodes it should work like a normal marker/turn light…

mx107marlin

Joined: Aug 12 2007
Posts: 3095
Location: Fairborn, OH
Post Tue Jan 22, 2008 9:52 pm

Acey, if you use the classic “Electricity is water” analogy, the Diodes act as a 1-way valve… they let electricity run through them unrestricted one way (It acts like a conductor) and the other way it prevents current flow (acts like a resistor)

So basically, If you wired this circuit up and left out the 4 Diodes, if you turned your running lights on, all 6 Turn signals (Front Back and Side on both sides) as well as your regular running lights would light up. Then, when your Left turn signal was activated, your 3 Left turn signals would flash, as well as your front and rear running lights. Same goes for the Right side.

So without them, the whole system kinda goes haywire, they keep the sections separate.

Hope that explains it a little better, although Black DX did a great job.

As for your other questions, the Resistor is what dims the signal for the running light part, that way if your Turn signals are on with the running lights off, they get a full 12 volt strobed from the turn signal wire. When the running lights are on, the resistor will lower the voltage to around 6V or half brightness. When the running lights are on and the turn signal is on, the voltage will flash from 6V to 12V and back, rather than the normal 0V to 12V and back.

Black DX

Joined: Oct 16 2007
Posts: 1007
Post Wed Jan 23, 2008 1:06 am

if I’ve used the program right, to get the lights to drop down to 8volts (to make them dimmed) you’d need a 150ohm resistor… I have a feeling at half brightness the lights won’t be as functional as running markers but at 6 volts a 220ohm resistor would be needed. Hope this works/helps…
Acey

Joined: Sep 01 2007
Posts: 117
Location: Calgary
Post Wed Jan 23, 2008 8:00 am

Thanks guys, I think I have all the information I need now. Thanks for the writeup mx, it makes much more sense now.
chrias

Joined: Mar 02 2008
Posts: 4
Post Sun Mar 02, 2008 3:48 pm

I was wondering, if you were to hook it up to the brake light as well, how do you isolate the brake from the turn signal. The reason I ask is because when I turn on the indicator and I step on the brake the it goes solid. It will only flash when I release the brake.
PwrRngr

Joined: Jul 19 2007
Posts: 4407
Post Sun Mar 02, 2008 4:39 pm

chrias wrote:
I was wondering, if you were to hook it up to the brake light as well, how do you isolate the brake from the turn signal. The reason I ask is because when I turn on the indicator and I step on the brake the it goes solid. It will only flash when I release the brake.

Use a diode.

chrias

Joined: Mar 02 2008
Posts: 4
Post Sun Mar 02, 2008 5:13 pm

I have one diode each on the brake and turn signal wire. The turn signal on my truck is a dedicated turn signal.
PwrRngr

Joined: Jul 19 2007
Posts: 4407
Post Sun Mar 02, 2008 8:35 pm

I read your question wrong, look into some logic gates. That would be the easiest way.
chrias

Joined: Mar 02 2008
Posts: 4
Post Sun Mar 02, 2008 8:48 pm

Forgive my ignorance but what is a logic gate? I’m more mechanically knowledged than electrical. lol
PwrRngr

Joined: Jul 19 2007
Posts: 4407
Post Sun Mar 02, 2008 9:09 pm

It’s a logic gate that will “filter” signals. Look into exclusive or gates (XOR Gate). Here’s a basic diagram.
User posted image
chrias

Joined: Mar 02 2008
Posts: 4
Post Mon Mar 03, 2008 6:48 am

Thanks, I’ll look more into it.
Acey

Joined: Sep 01 2007
Posts: 117
Location: Calgary
Post Mon Mar 03, 2008 6:57 am

Once you start stringing relays together you can pretty much do anything you want, electrically. At the moment, I’m looking into white flex LED strips as DRL’s (Audi R8 style) that come on automatically under two conditions. 87a from my running lamp relay (so they shut off when I turn my headlight switch one notch) goes into a second relay as the constant source, and 12V+ from an add-a-circuit in the BCM fuse is the trigger for the second relay (so they come off when the key comes out). This should be sweeeet if I ever get it hooked up.
blue one

Joined: Jan 27 2008
Posts: 573
Location: Las Vegas
Post Mon Mar 03, 2008 4:22 pm

man you guys are good.
Acey

Joined: Sep 01 2007
Posts: 117
Location: Calgary
Post Mon Mar 03, 2008 10:13 pm

blue one wrote:
man you guys are good.

Hey you ever explain how you get those wheel wells so damn bright? Those just flex strips?

And yeah everything I’ve learned about automotive wiring/lighting I’ve learned here. These guys are the best of the best.