My 2007 GS350 will no longer respond to either of my key fobs but will start and run with the mechanical key. What is likely to be wrong?

[Henry Whitmore]

My 2007 GS350 will no longer respond to either of my key fobs but will start and run with the mechanical key. What is likely to be wrong?

[dcfish]

Fob batteries ? Disconnect the neg. terminal for 10 minutes after you replaced $8.00 worth of Energizers  😉

[Bykfixer]

From what I understand the fob did not have much range when batteries were new and as batteries get weaker the range gets shorter and shorter. 

My 04 fob stopped working because my car thinks one of the doors is ajar. The door was dinged and that caused the open/closed sensor to malfunction. So there are instances where the fob is "blocked" from locking or unlocking the doors. 

But like DC said it could be the old batteries.