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Where to tap brake light power for diffuser brake light?
I see a bunch of wire taped up that runs from left to right, right in the diffuser area. I really hope brake light wire is in there, if so what colors are the pair?
I see a bunch of wire taped up that runs from left to right, right in the diffuser area. I really hope brake light wire is in there, if so what colors are the pair?
Hello, did you find an answer where to wire the break light to? Same question on my W205.
Just tap into the third brake light. It easier to find the wires.
not a bad idea but I’m struggling to get to it. Any tips? I’ve got trim removal tools that got up the plastic enclosure but only facing me, it’s still attached at the glass. I tried to go under the hard fabric liner and struggled there too haha.
Remove your third brake light housing and tap it from the connector wire.
can I just remove the small plastic housing or does the entire fabric piece above the seats need to go to? I struggled and gave up so far to get either off
I don’t have the same car as your. But to access to the wire, I would think you need to remove the brake light housing.
If anyone knows what to do, I’m so confused. I was able to wire to my real driver’s side fog light circuit in the tail lamp assembly and everything seems to function as normal. It was tricky getting to 3rd brake lamp so I gave up on that btw. Anyway, the light works flawlessly when the engine is off! When I turn the engine on the light stays on for a few seconds then completely fades to dark in about a second. Could anyone please help pinpoint the issue? I suspect there is a voltage issue when car engine is on though my car’s original fog lamp remains lit without issue so that indicates there is at least enough voltage for that and it doesn’t throw any errors on my dash. I’m so confused.
I don’t have the same car as your. But to access to the wire, I would think you need to remove the brake light housing.
Hello, could anyone help explain what may be the issue? I have a rear diffuser lamp wired into my fog lamp circuit within drivers side tail lamp (center mount was tricky to get to) . It works with the engine off but not on. See video:
Hello, could anyone help explain what may be the issue? I have a rear diffuser lamp wired into my fog lamp circuit within drivers side tail lamp (center mount was tricky to get to) . It works with the engine off but not on. See video: https://youtu.be/qUIVM4r04Q0
I don’t understand, I’ve checked my ground. Is there a voltage issue, how do I fix it?
I end up having a shop install the diffuser and asked them to get the light wired, they've tapped from the tail light like how you are about to do, I can take a look to see if the wiring can be shown easily, if so i'll post a pic. I know that the diffuser light I have has its own logic, so your might too. Meaning, when I brake, it flashes first then stays on. The alternative setting is to do something else that I forgot. Maybe you need to check your settings on that also.
Thanks, yeah it doesn’t seem to be an issue with the diffuser light. Mine has a yellow wire coming out in addition to the black ground and red power. The yellow just makes it flash but neither work when engine is on for a few seconds. It seems to be a slow and flickery fade out of the light (can’t really tell on video) so that leads me to believe voltage is a bit different with engine on. I’m also a bit curious if the thin wiring from the diffuser is having resistance issues with the thicker wire I tapped into the light with? Hmm.
Originally Posted by TLDream
I end up having a shop install the diffuser and asked them to get the light wired, they've tapped from the tail light like how you are about to do, I can take a look to see if the wiring can be shown easily, if so i'll post a pic. I know that the diffuser light I have has its own logic, so your might too. Meaning, when I brake, it flashes first then stays on. The alternative setting is to do something else that I forgot. Maybe you need to check your settings on that also.
Hi there I was curious if you were able to see how your’s is wired up. I wonder if it’s just the fog lamp circuit giving me issues but also it’s a big pain to test circuits. Would appreciate knowing which colors of wire your shop tapped into as this is driving me nuts haha. Thanks!
I had to rip the tape out to get this picture for you
its the brown and cyan/green cable. black to brown, red to cyan/green. test it before you trust it.
Thank you so much for your help! I wired it up like your’s and it works great! I originally wanted the light for rear fog lamp purposes but I think I like it better as a brake lamp anyway!
Darn. I guess I spoke too soon. I just realized that my diffuser light flashes with my left blinker now. Do you not have this issue wiring to the wires you did? I used a different ground source instead of brown wire but I can’t imagine that caused it? My diffuser light mystery continues
Originally Posted by TLDream
I had to rip the tape out to get this picture for you
its the brown and cyan/green cable. black to brown, red to cyan/green. test it before you trust it.
Does anyone know the answer to this question? As I’ve search and keep coming up with dead ends. I’ve just installed a real diffuser with a third brake light and realized you cannot tap the brake lamp without being affected by the turn signals. Can’t seem to find the wires for the third brake light on rear deck
Does anyone know the answer to this question? As I’ve search and keep coming up with dead ends. I’ve just installed a real diffuser with a third brake light and realized you cannot tap the brake lamp without being affected by the turn signals. Can’t seem to find the wires for the third brake light on rear deck
If you ever do figure out the answer please let me know. I’ve also hit nothing but dead ends and wired the diffuser light in to my front light bar. I also have a DMP design rear light bar that I would like to wire into the lights without it blinking with one turn signal but struggled and gave up on getting to center mounted’s wiring. Such a hassle.
If you ever do figure out the answer please let me know. I’ve also hit nothing but dead ends and wired the diffuser light in to my front light bar. I also have a DMP design rear light bar that I would like to wire into the lights without it blinking with one turn signal but struggled and gave up on getting to center mounted’s wiring. Such a hassle.
i’d most definitely well, so far we track down the light on the rear deck has a harness that plugs into the main harness in the trunk, we already know the color for the wiring harness we just need to figure out when it comes out from the rear deck and goes into the trunk, which wiring harness does it go to. Keep you posted
I was able to tap the third brake light directly and run the wire back out into the trunk, but I get a little bit of flickering when I go from drive to reverse. I tried your wire tap and it a much brighter signal with no flickering……but unfortunately you may want to check yours … with my right turn signal on it make the diffuser brake light flash also
Last edited by Griley; Sep 27, 2021 at 05:58 PM.
Reason: Tried
I was able to tap the third brake light directly and run the wire back out into the trunk, but I get a little bit of flickering when I go from drive to reverse. I tried your wire tap and it a much brighter signal with no flickering……but unfortunately you may want to check yours … with my right turn signal on it make the diffuser brake light flash also
i know I think the best way to fix that is to connect the yellow wire to the trunk taillight
i know I think the best way to fix that is to connect the yellow wire to the trunk taillight
The yellow wire ? Instead of connecting the red? I have 3 wires, red is signal for brake light
yellow is if you want the brake light to flash 5 times before going solid, and black is ground.
Mines is the sedan, so no trunk light. How are the c63 guys doing this ? The wiring should be the same for the most part
The yellow wire ? Instead of connecting the red? I have 3 wires, red is signal for brake light
yellow is if you want the brake light to flash 5 times before going solid, and black is ground.
Mines is the sedan, so no trunk light. How are the c63 guys doing this ? The wiring should be the same for the most part
To be honest I’m not sure. I know how to fix the problem with the yellow wire.
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