I have some if you need a new one but if you bought a brand new board and it doesnt work I don't think the board is the problem. The brake lights work on the taillights? (I don't remember the circuit but I think the running lights are irellevant. Make sure the BRAKE lights still work)

 

All brake lights work, EXCEPT for the high-mounted brake light (no spoiler). I actually got the oem replacement USED, not new as in my first post. Perhaps the replacement light is out too? I checked the wiring and it all seems normal and not spliced anywhere. Does this give you a better idea of my issue?

 

Best bet is to ensure your third brake light is getting proper ground and good 12v with a multimeter. You can also bench test your third brake light with a 12v power supply.

If it does turn out that the brake light is bad I can help you out with a new one

 

So if i test my light and it doesnt work, i need your mod, right? I connect light to the battery and it didn't light up. Noob here.

 

I would test to make sure the brake light is getting power - its just 2 pins.

All I can say is that my light will work when power is applied to it

 

I get 12V at the connector so looks like my brake light is bad! Sign me up for a new light!

 

OK Ill PM you

 

Still making this?

 

I bought the LEDmarkers interior "3rd tail light" LED replacement for my 03 G35 Coupe. Got it quickly from the vendor, but there are absolutely NO instructions on how to access/remove the rear deck lid 3rd tail light housing. This is very complicated process and the LED strip replacement product is utterly useless without these pertinent instructions. Also, their "instructions" via someone else's youtube video does not link to a video addressing the removal process in a coupe. At present it looks like I will be returning the product due to this lack of information.

 

Its not that bad - I like to remove the rear seat and remove the rear deck. ledmarkers is out of business though from what I can tell so I dont think youll have good luck returning it.

 

After fiddling around in the coups trunk and dropping the upper liner (as seen on youtube video for the sedan), I went into the cabin and simply used a large flat head screw driver to lift the third tail light mounting. It is simply a snap in/on housing like it should be. There is NO screw securing the housing from inside the trunk.

It took a bit of fitting but the LED sold to me by LEDmakers was installed and is working.

So, from what I remember, there is no real need to mess with the trunk liners in the G35 coupe at all. Just carefully lift the housing from inside the cabin with something thin and flat so that no gouge marks are left.

I guess I got lucky cause they send me the correct product lickety split.