What is a wire that connects to a wire on the bike but it doesn’t do anything? There’s a button on the side that you press but it’s not performed electronically, please advise what’s the wire for?

I'm trying to change out this phone caddy and see that there's a cable coming out of the caddy itself. Can anyone help so I can determine where the cable actually goes.

aside from it taking over two weeks to get from china, it fits and works as expected. easy to install hook g this one lasts longer than 3 months

Thank you for the replacement.
I'm very happy