There's more than just a simple TSB for this...there was a recall notice. Did the dealer check if your VIN is among the list of affected vehicles.
https://g35driver.com/forums/g35-sed...ll-letter.html
https://g35driver.com/forums/g35-sed...ag-sensor.html

 

Yeah I thought it was part of the recall or atleast a TSB so I brought it up the dealer on the second visit (I'm on my third now). They looked it up by VIN number and said that my model was unaffected (it was manufactured in the end of 06.

Update to my last post, I had a chance to sit down with the Infiniti tech who told me that when they did the recall, none of the inifiniti vehicles that came through this dealer registered a problem. It was mostly the Altima brand that experienced the issue. He also agreed that he would do the same checks associated with the recall to see what kind of results he got.

I got a call later that day from the dealer and they agreed with Infiniti tech support's advice to replace the seat with the sensors which has fixed "similar" problems in the past. They were unable to reproduce the problem themselves but I was pretty clear that I was considering it a serious safety issue. I'm grateful they are doing this, except the service manager was telling me this as if they were doing me a favour. That being said he is a pretty good guy and has been helpful in the past so I'm glad they're sorting it out under warranty.

I tried to have my passenger shift their weight and lean to one side to see if it made a difference in case it was the sensor in the thigh rest. So far it hasn't worked but we'll see what the next seat does.

 

My 07 G35S had to have its seat sensor replaced under the factory recall. The dash light would indicate a failure in the sensor or circuit. Weight of passenger had nothing to do with the failure mode.

 

Interesting.... Come to think of it this morning my passenger air bag sensor light kept coming on and off. I was on the verge of punching the car in the face because quite honest the last thing I want to deal with is a defective sensor but after reading this post I realized I put some stuff on the front seat so maybe because there was a little weight on the seat and it possbly assumed it was a small child. HOPEFULLY!! I am anxious to drive my car again to see if the light comes on again with nothing on the seat.

I pray to the car gods and the holy lord himself that its not a stupid sensor that I need to fix and pay for out of pocket....

 

Yep putting something small and light in weight will have the sensor go off.