Infiniti G35 Sedan dead battery 5 times in four months -help!

Infiniti G35 2003 Sedan (original owner) keeps having a dead battery. After the second time we replaced the battery. On three following occasions, we called AAA to jump it and took it to the dealer. They can find nothing wrong. Any ideas out there? The charging system checks out fine as do the battery and alternator. The thinking is something is draining the battery. Suggestions have been is it the sunroof? the bose speakers? the trunk light? the light on the spoiler? leaving the headlights on? None of these have been the key to solving the mystery. Any ideas?

Has anyone put a amp gauge on the battery with everything turned off? If not that is the place to start.

Agreed. This is the standard way of tracking down this sort of problem, once the alternator has checked put.

BTW, why are you going to a dealer for this kind of work? He is more expensive and, as you can see, not particularly effective. Find a good independent shop.