Just picked up my Gun Metallic SR last Monday. Lease was up on my 13 Altima 3.5SL. Absolutely love the MAX!!!
Noticed the other night an almost "white noise" coming from the rear seating area of the vehicle when I turned the radio off. Thought maybe it was the heater, nope that was off too. Its not too loud of a noise and I haven't noticed it before as I usually have the radio on, but kind of bugging me knowing that its there. I couldn't pinpoint exactly where its coming from (even after climbing in the back between the kids car seats, I'm 6'5" so it wasn't easy). Could this be the active noise cancellation?

 

The seat heating/cooling system has a blower that makes similar noise when turned on. Was your seat heating on?

 

It was on when I first noticed it. That was the first thing I thought of. I turned the system off and it was still there. Even the next morning when I started the car and the system was off.

 

Are you sure its not coming from the speakers on the rear doors...the tiny ones. Try getting pretty close to it. If not fold the rear seat to check if you can hear coming from the rear speakers. It has to be from the speakers...cant imagine where else it could be coming from.

 

I've got a few days off from work coming up and will try to narrow it down more. The radio was off so not sure why there would still be sound coming from the speakers. I was parked in the driveway so I know its not road noise.

 

The Noise Cancellation System is mostly in the passenger compartment headliner, and that is one reason we probably should not be making mods that require cutting into the headliner. As I understand this NCS system, it detects sound frequencies it considers to be unpleasant, and puts out supposedly inaudible frequencies that tend to cancel the effect of frequencies it has detected. But I am no expert on this stuff.

 

Ok, narrowed it down. It's coming from under the middle of the back seat. And it's happening when the engine is off and just the accessory power on. So now I'm thinking fuel pump. Looks like a trip to the dealer is in order now.

 

Great detective work! Knowing the sound is there when the car is sitting with the engine off and just the accessory power on really narrows the possibilities way down. If your dealer is on the ball, this should be fixable in fairly short order.

 

I get the same noise. Turned everything off and i still hear it. Ill have to check by my rear seat.

 

Thanks DarkSlate. Confirms I'm not going crazy and hearing things. I just have to find a day to get it into the dealer now.

 

Just an update for everyone. After taking a trip to the dealer to have some other things looked at. Turns out it is normal. When the seat heater/ac is activated it turns on a fan that ventilates the seats. Sure enough, turn off the climate control on the seat and you hear the fan turn off, turn it on and the fan turns on. I had an "I'm and idiot" moment with the dealer about it, but at least I know its normal.