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Old 08-29-2010 | 03:27 AM
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Rear LED Turning Signal Lights?

Hey everyone, sorry for all the questions that ive been posting! This time, i just wanna know if anyone installed LED turning signal lights at the rear end? I tried buying a pair of those LEDs, but once i installed it, it just flashes way faster than it should with the normal bulb. I was wondering if anyone bought LEDs signal light and have the same flashing effect of maybe about 1 flash per second? Thankss =)
Old 08-29-2010 | 11:13 AM
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Leds run on much less voltage than do filament bulbs. When you put the led bulb in, it may only require 3 volts or so to light up, so your car thinks that the normal 12v requiring filament bulb is out and thus blinking faster to tell you a bulb is out. You need to install an inline resistor made for this. Check out v-leds.com and go to blinker fix's. A pair of 3 ohm inline resistors should increase the voltage the car sees and make if blink normal.
Old 08-29-2010 | 01:27 PM
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^ +1. you need to add resistors. what bulbs are you using? i havent found an led bulb that is bright enough for daytime use
Old 08-30-2010 | 12:37 PM
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Originally Posted by beerme986
what bulbs are you using? i havent found an led bulb that is bright enough for daytime use
This is the most significant issue to overcome when replacing bright incandescent bulbs with LED's. License plate lights are easy, but turn signals and brake lights need to be substantially brighter.

That said, I've been very happy with V-LEDs 7W Red LED 7440 bulb. With seven Watts of red LED light (that's a LOT), I actually think it is brighter than the incandescent it replaces. They aren't cheap though
Old 09-03-2010 | 12:58 AM
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To slow the blinking down, they have resistors for that you can get at Autozone or other auto parts place. I think its like a 6 Ohm resistor that handles like 50 Watts or so. And just connect one side of the resistor to the positive and one side to the negative of the leads heading to the bulb. One for each side of course.
Old 09-03-2010 | 12:59 AM
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Theyre called load resistors.

The 3ohm isnt enough you need the 6ohm.
Old 09-03-2010 | 11:25 AM
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Why put LED's in the rear for turn signals .... the bulb is behind red plastic anyhow. Can you really tell much of a difference between a LED bulb or incandesent behind that much red plastic?
Old 09-03-2010 | 12:15 PM
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Originally Posted by 2008G-Man
Why put LED's in the rear for turn signals .... the bulb is behind red plastic anyhow. Can you really tell much of a difference between a LED bulb or incandesent behind that much red plastic?
The purpose of using LEDs in turn signals is not to showcase how a different bulb looks or even its color, but rather to showcase how FAST LEDs switch on and off. In a turn signal application, the fast speed of LEDs is very distinctive and more visually noticeable - in the same way that the new cop car red/blue flashers are more noticeable. By comparison, incandescent bulbs seem to slowly fade on and slowly fade off.
Old 09-03-2010 | 12:20 PM
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Originally Posted by STOOF
The 3ohm isnt enough you need the 6ohm.
Correct. The load resistors need to provide the same power load that an incandescent turn signal bulb would, which is around 21-25 Watts. If you pick 24 Watts as a nice round number, the formula for resistance is:

R = (Voltage)^2 / Power = 12V*12V / 24w = 6 ohms

Then, of course, you can't just buy any old 6 ohm resistor. In this application, the resistor has to withstand and dissipate the heat generated by absorbing 24 Watts of power. That's a "Load" resistor.
Old 09-09-2010 | 12:46 AM
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I used red smt leds with the load resistors
Old 12-10-2010 | 04:14 PM
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If I change out both front and rear blinkers, I only need to put resistors in either the front or the back right?
Old 12-10-2010 | 06:53 PM
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Never thought about the fading in and out of incandescent bulbs.
Here's a video comparison. YouTube - 2006 BMW M6 Turn Signal upgrade to LED turn signals
Skip to 0:45.
Old 12-10-2010 | 08:36 PM
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Originally Posted by lzzhang10
If I change out both front and rear blinkers, I only need to put resistors in either the front or the back right?
No, you need resistors for both front blinkers and rear blinkers.
for a total of 4 resistors

Check out V-leds, they have information about it.
Old 12-11-2010 | 01:38 AM
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Originally Posted by tbone12
No, you need resistors for both front blinkers and rear blinkers.
for a total of 4 resistors

Check out V-leds, they have information about it.
acutally I just installed them in the front and it stopped hyper blinking both in front and back.
I used these:3 OHM 50W 4 BULB LED LOAD EQUALIZER RESISTORS TURN SIGNAL BLINKER FIX

I guess 1 pair is enough for these resistor from v-leds
Old 01-11-2011 | 12:19 PM
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Originally Posted by lzzhang10
acutally I just installed them in the front and it stopped hyper blinking both in front and back.
I used these:3 OHM 50W 4 BULB LED LOAD EQUALIZER RESISTORS TURN SIGNAL BLINKER FIX

I guess 1 pair is enough for these resistor from v-leds
Really—that 3 OHM worked for front and back? Awesome!

Where up front did you mount the resistor? I know they get hot and cannot be screwed into plastic.



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