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Discussion Starter · #1 ·
Hello again. So I got a strobe light module (Brake Light Strobe Module | Super Bright LEDs) as well as an led all for the third brake light. I plugged the new led in real quick and it worked fine but then the dash light came on unfortunately, so is there any led I can get that won't trigger the dash light?

Also, as far as wiring up the strobe module for the third brake light, I was just going to splice it right before the plug connected to the car, so I can retain the easy removal of the third brake light assembly. There are two wires coming from the module that will run towards the car (I believe), and only one positive that goes toward the light (where the plug will be). So will I have an unattached negative??

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Also, just to make sure, is the green and yellow striped wire the positive one?

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Thanks for any help.
 

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Mr. Roo
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I wonder if a "brake light out module" from a car that didn't use a window light would work. But it's easier to just remove the bulb-out light in the dash. You could go to all the trouble of installing a resistor with the window light, but that just wastes energy.

The only wire you will cut will be the positive. The positive from the car goes into the module, and then out of the module to the brake light. The negative ground does not get cut, but still goes directly to the brake light. The module needs to be grounded, which can be done to the body or splicing into the ground wire.

I'm not sure which is which, but I would 100% start with the green/yellow wire being positive. Just test it first.
 

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I wonder if a "brake light out module" from a car that didn't use a window light would work. But it's easier to just remove the bulb-out light in the dash. You could go to all the trouble of installing a resistor with the window light, but that just wastes energy.

The only wire you will cut will be the positive. The positive from the car goes into the module, and then out of the module to the brake light. The negative ground does not get cut, but still goes directly to the brake light. The module needs to be grounded, which can be done to the body or splicing into the ground wire.

I'm not sure which is which, but I would 100% start with the green/yellow wire being positive. Just test it first.
Yes the brake light out mod will be needed.
 

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Discussion Starter · #5 ·
I wonder if a "brake light out module" from a car that didn't use a window light would work. But it's easier to just remove the bulb-out light in the dash. You could go to all the trouble of installing a resistor with the window light, but that just wastes energy.

The only wire you will cut will be the positive. The positive from the car goes into the module, and then out of the module to the brake light. The negative ground does not get cut, but still goes directly to the brake light. The module needs to be grounded, which can be done to the body or splicing into the ground wire.

I'm not sure which is which, but I would 100% start with the green/yellow wire being positive. Just test it first.
Thank you for clearing that up for me. As far as grounding the module goes, I was leaning towards splicing into the existing ground wire (which is just the grey/tan wire right) using a t-tap connector. I think that may be easier, but I'm just worried about the lack of space back there, oh well. I'll also be sure to test the wires to make sure I know which is which.
 

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Discussion Starter · #6 ·
Yes the brake light out mod will be needed.
I think I'll just end up taking out the dash bulb or leaving the warning light on. Its a shame though I really like that feature but like Tobias pointed out, it would be more work and more importantly a waste of energy. Not like anything on this car is energy efficient anyways though...
 

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Discussion Starter · #7 ·
Strobe brake lights are one of the worst looking things ever invented
Well I think they look pretty good as long as I'm not the one behind them. Lol but really, I'm hoping it'll grab people's attention and dissuade them from tailgating because I really can't stand that. Also, here in South Carolina theres a lot of huge SUVs and squatted trucks you have to worry about rear ending you.
 

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Mr. Roo
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Thank you for clearing that up for me. As far as grounding the module goes, I was leaning towards splicing into the existing ground wire (which is just the grey/tan wire right) using a t-tap connector. I think that may be easier, but I'm just worried about the lack of space back there, oh well. I'll also be sure to test the wires to make sure I know which is which.
That's what I did with mine, T-tapped the ground wire into the existing ground. Actually, let me get a picture.

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Ah yes, so you can see I grounded mine to the black/white wire. So yes, the black/white wire on yours is the ground. You can also see how I split up the green wire to go into and out of the module with the red/yellow wires.
 

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Discussion Starter · #9 ·
That's what I did with mine, T-tapped the ground wire into the existing ground. Actually, let me get a picture.

View attachment 138001

Ah yes, so you can see I grounded mine to the black/white wire. So yes, the black/white wire on yours is the ground. You can also see how I split up the green wire to go into and out of the module with the red/yellow wires.
Perfect. So I could tap into the ground anywhere, right? I was thinking of putting the t-tap connector close to the actual brake light where I'll do the other splice so I could stuff the module underneath, as there is a good bit of space there.
 

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like Tobias pointed out, it would be more work and more importantly a waste of energy. Not like anything on this car is energy efficient anyways though...
The amount of energy wasted on account of a load resistor for your LED brake lights would be equivalent to 0.0001 mpg.

Also, here in South Carolina theres a lot of... squatted trucks....
My friends and I call it bitch-doggin'.

WTF is up with this fad?? Where did it come from? Why? I really, really don't get it. My theory is basement-dwelling, video-gamer kids saw real men's trucks doing real work with actual loads in their beds/trailers - so they decided to emulate the look of a real man's truck by lowering the back and perhaps lifting the front.

Not too many of them around these parts, but when one is behind me, it motivates me to install a rearward-facing 250w PIAA spotlight.
 

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Discussion Starter · #11 ·
The amount of energy wasted on account of a load resistor for your LED brake lights would be equivalent to 0.0001 mpg.



My friends and I call it bitch-doggin'.

WTF is up with this fad?? Where did it come from? Why? I really, really don't get it. My theory is basement-dwelling, video-gamer kids saw real men's trucks doing real work with actual loads in their beds/trailers - so they decided to emulate the look of a real man's truck by lowering the back and perhaps lifting the front.

Not too many of them around these parts, but when one is behind me, it motivates me to install a rearward-facing 250w PIAA spotlight.
Hahaha. Thats really funny man. Yeah I wouldn't mind having a huge rear facing spotlight either, might help fend off the entitled suburban drivers. One plus to come from the squatted truck community is that surprisingly they seem to have realized they've severely handicapped their drivability, and therefore, take slower turns and keep back further distances because they have terrible body roll and poor vision. So in a sense, it made a lot of foolish people better drivers. I guess the appeal is worth it for the monthly truck shows and attention around town, but honestly at this point, the shock value is dying off. It seems almost 1 of 4 trucks are squatted nowadays. Quite ridiculous.

As far as the load resistor is concerned, if installed, would this allow the dash light to work normally (meaning it would turn on when the LED eventually died), or would it cause enough current to always fool the car into thinking the light wasn't out?
 

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As far as the load resistor is concerned, if installed, would this allow the dash light to work normally (meaning it would turn on when the LED eventually died), or would it cause enough current to always fool the car into thinking the light wasn't out?
Good questions. I'm not certain how the light-out functionality works, but the way I see it, there are only two ways for the body control module to diagnose the circuit for a functional lamp... Either it measures the resistance of the circuit or it calculates current flow via a pull-up resistor and voltage divider scheme.

If the car is off and you remove the brake light bulb - does the car immediately recognize the missing/burned-out bulb upon key-up? Or, do you have to first apply the brake for the car to recognize it?

If it recognizes the missing bulb before you even touch the brake, then the body control module is likely measuring the resistance of the circuit all the time - and the load resistor would prevent the dash light from ever coming on, on account of that circuit - regardless if the LEDs were functioning properly or not.

If the missing bulb feature requires you to press the brake pedal for it to recognize the missing bulb, this implies the BCM has a pull-up resistor in it so that it can calculate current flow thru the circuit. In this case, the dash light should work properly - because if the LEDs burn out, they wouldn't call on the circuit for any current flow.

Either way, the load resistor would only cause "wasted electricity" when the brake lights are being illuminated. If the brake lights are burned out (whether incandescent or LED), there will be no current flow, and thus no "wasted electricity".
 

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Discussion Starter · #13 ·
Good questions. I'm not certain how the light-out functionality works, but the way I see it, there are only two ways for the body control module to diagnose the circuit for a functional lamp... Either it measures the resistance of the circuit or it calculates current flow via a pull-up resistor and voltage divider scheme.

If the car is off and you remove the brake light bulb - does the car immediately recognize the missing/burned-out bulb upon key-up? Or, do you have to first apply the brake for the car to recognize it?

If it recognizes the missing bulb before you even touch the brake, then the body control module is likely measuring the resistance of the circuit all the time - and the load resistor would prevent the dash light from ever coming on, on account of that circuit - regardless if the LEDs were functioning properly or not.

If the missing bulb feature requires you to press the brake pedal for it to recognize the missing bulb, this implies the BCM has a pull-up resistor in it so that it can calculate current flow thru the circuit. In this case, the dash light should work properly - because if the LEDs burn out, they wouldn't call on the circuit for any current flow.

Either way, the load resistor would only cause "wasted electricity" when the brake lights are being illuminated. If the brake lights are burned out (whether incandescent or LED), there will be no current flow, and thus no "wasted electricity".
Thank you so much. The light comes on when I tap the brakes for the first time during a commute, not immediately upon start, meaning there is a pull-up resistor then. With that established, I may consider implementing a load resistor.
 

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Mr. Roo
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The light does come on the first time the brakes are tapped. But I doubt that the LED draws enough power for the sensor module to notice. My guess is that installing a resistor on there will fool it enough that if the LED did die, the light wouldn't come on because the resistor is still drawing enough power. However, the light would still function and come on if one of the other rear stop lamps were to burn out. That would be the benefit to using a resistor. However, I did all LEDs on mine, so the warning light was completely useless at that point, and I did enjoy not having all the rest of the lights in the car dim when the brakes were pressed, due to the significantly lower current draw without bulbs and resistors.

And yes, you can tap into the ground power anywhere, so just do all the wiring for the flasher module inside the window brake light housing where there is plenty of space.
 

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Discussion Starter · #15 ·
The light does come on the first time the brakes are tapped. But I doubt that the LED draws enough power for the sensor module to notice. My guess is that installing a resistor on there will fool it enough that if the LED did die, the light wouldn't come on because the resistor is still drawing enough power. However, the light would still function and come on if one of the other rear stop lamps were to burn out. That would be the benefit to using a resistor. However, I did all LEDs on mine, so the warning light was completely useless at that point, and I did enjoy not having all the rest of the lights in the car dim when the brakes were pressed, due to the significantly lower current draw without bulbs and resistors.

And yes, you can tap into the ground power anywhere, so just do all the wiring for the flasher module inside the window brake light housing where there is plenty of space.
Yeah that was my worry with the resistor. I keep going back and forth between installing one or not, but I know that I plan on installing at least one more set of LEDs (reverse lights) in the rear, so that would be two more resistors (I believe) to allow the system to function properly with the regular tail lights, and I just get so hesitant with throwing around multiple resistors.
 

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Mr. Roo
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Yeah that was my worry with the resistor. I keep going back and forth between installing one or not, but I know that I plan on installing at least one more set of LEDs (reverse lights) in the rear, so that would be two more resistors (I believe) to allow the system to function properly with the regular tail lights, and I just get so hesitant with throwing around multiple resistors.
Ah no worries with the reverse lights. Those don't trigger the bulb warning I think, I think it's JUST the brake lights. I've never heard of it ever warning about any other light. Not the reverse, not the tails. The signals have their own warning method. Probably because you can check all the other bulbs yourself, not the brakes. I'm not sure. But I wouldn't worry about it. Though , you could try. Just take out one of the reverse bulbs, go in reverse, and see if the dash lights up.
 

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Discussion Starter · #17 ·
Ah no worries with the reverse lights. Those don't trigger the bulb warning I think, I think it's JUST the brake lights. I've never heard of it ever warning about any other light. Not the reverse, not the tails. The signals have their own warning method. Probably because you can check all the other bulbs yourself, not the brakes. I'm not sure. But I wouldn't worry about it. Though , you could try. Just take out one of the reverse bulbs, go in reverse, and see if the dash lights up.
Oh nice. I want to get really bright reverse lights as I always back into my (somewhat) long driveway and can barely see at night. Maybe I get that huge spotlight Hodgdon was talking about lol.
 

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So, when it comes to swapping the reverse bulbs for a set of LEDS that will be bright enough to light up the road behind you (hopefully) I have some tips. First of all, be realistic with your expectations. Thinking it's going to light things up like a set of low beam headlights is absolutely NOT going to happen, even if you installed actual headlight bulbs. Unfortunately the reverse light reflectors are too small and on top of that only designed to output light straight backwards similar to a flashlight beam. In order to light things up like a headlight you need a reflector that spreads the beam out more. Simply buying a set of LEDS with crazy high lumen output WILL NOT get you the results you want and waste a lot of money on the process. Trust me, I tried three different sets myself before figuring all this out. If you want the reverse lights to be similar to a spotlight then that's exactly what you need to buy and mount them facing backwards. That's the only way, at least on gen 1 models.
 

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Discussion Starter · #19 ·
So, when it comes to swapping the reverse bulbs for a set of LEDS that will be bright enough to light up the road behind you (hopefully) I have some tips. First of all, be realistic with your expectations. Thinking it's going to light things up like a set of low beam headlights is absolutely NOT going to happen, even if you installed actual headlight bulbs. Unfortunately the reverse light reflectors are too small and on top of that only designed to output light straight backwards similar to a flashlight beam. In order to light things up like a headlight you need a reflector that spreads the beam out more. Simply buying a set of LEDS with crazy high lumen output WILL NOT get you the results you want and waste a lot of money on the process. Trust me, I tried three different sets myself before figuring all this out. If you want the reverse lights to be similar to a spotlight then that's exactly what you need to buy and mount them facing backwards. That's the only way, at least on gen 1 models.
Thats a really good point. I was also considering 2 other options besides bright reverse leds, the first of which being to wire the inner tail lights up as reverse fogs. I've always wanted this function but I don't want to give up them serving as regular tail lights. I think I read somewhere that you can wire them to still work as tail lights and have the ability to get super bright, but I can't recall/find the article at the moment.

The second option I was considering (which is almost ricey in my opinion) would be to install a small license light bar, such as this one (Amazon.com: VLEDS 1800lm 5500K White LP-Reverse License Plate Backup Light System Black Satin Finish 72 LED: Automotive). I feel like at that point though I might as well wire up any set of bright leds and make it work but I'm just not the biggest fan of adding stuff like that, especially if I could get the rear fogs to work.
 

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Mr. Roo
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I had an older version of the VLEDs LP-reverse light on mine. It worked lol, after all the wiring and drilling. But I'm in the same boat with my new car, and I don't want to do permanent drilling and have something stuck on looking to the license plate.

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