little red LED on key fob

[hotrodjohn71]

I have a 2010 Nissan Rogue.
On the master key fob there is a tiny red LED.
What is this LED for and how does it work?
Thanks

[hotrodjohn71]

To clarify, this is the key-shaped key fob, not the oval fob

[phmichel]

Either way it should be the indicator light when transmitting. Press a button and the little red light is on, right?

[hotrodjohn71]

I never noticed it in all these years. I thought it might mean the battery was low but transmitting indicator makes sense