Used 2005 G35 coupe 3rd brake light and spoiler light are out.
I'm new to this car hoping you all can help me in troubleshooting why this is not working.
FYI: I have no idea of what past owner has done to car or what changes could have been made.

Please help is this a common problem.

 

In my case (05 as well), it was the the wiring to the spoiler which was the problem. There's a part of the wire which rubs up against a sharp edge of the trunk.

 

Anybody has pic of where and how to rewire.

 

Well, for one thing, the car should have 1 light, and not both. So the fact that you have a 3rd brake light on the rear shelf, and a light in the spoiler means that a past owner added the spoiler.

Now, if they wired it up is another question. So without having the car in front of us, it's tough for us to see if the past owner cut the wires to the original light and wired the 3rd brake light, or never wired the 3rd brake light and the original light has burned out (common issue with G35's)

So basically step one is to open the trunk and see if you have wires going to the 3rd brake light.

BTW, a lot of ebay aftermarket OEM wings had crappy 3rd brake lights that burned out fairly easily. So partof your investigation will be to find out of your wing is OEM or an OEM-replica and if holes were drilled into the original trunk, or the owner swapped trunk lids.

 

Hmm. I need to check maybe again I know there are 4 holes when I open the trunk 2 on each side.