I have an 08 G35x and lately its been acting funky. When i go to my car the door wont unlock (have to get in with the key) and put the fob in the dock to get my car to start....it's been doing this alot lately, although sometimes it will work. I don't think it's the battery because i have switched key fobs and it is still doing it. Just getting frustrated not knowing when my fob will work or not, so does anybody have any clue as to why this is happening? Thanks

 

Well two things,
the remotes BOTH batteries could be low, because even though you only use 1, the signal of the second remote is always sending signal too, so the battery is in use from the moment you put it in,
so cheapest route would be to change both batteries, usually there is a red key light that flashes when the battery signal is weak....
secondly, there is an antenna in the trunk passanger side area under the carpet that bolts to the side of the 1/4 panel, it could be bad, unhooked slightly that's not an expensive part either, so either way it should be a realtively easy fix, sometimes the remotes just lose programming, and have to be reprogrammed (very rare)
so my first step would be to change BOTH remote batteries, and go from there

 

O ok i will try that, and if this doesnt work where can i find the antenna to replace it?

 

That's the easist thing in the world,
take your key blank out of the remote, you will see a little area where you could get a flat head screwdriver and pry it open, it splits in two, you will either have a CR2025 or CR2032 battery, make sure you identify the correct battery and replace it the way it goes, should be marked, with the battery you need, and which way the + goes, if that doesn't work, then I will post a image of the antenna for keyless entry here in a minute
~phil~

 

 

In the above Graphic, E and F both show to be Antenna, Smart Entry there are 2 different ones
E is 285E4-JK60A retail - $10.57
F is 285E5-JK60A retail - $29.45