So I've owned my tahoe for a while. It came with 2 3 button remotes. I never thought anything about it. Well recently I was cleaning the dirt out of the unlock button on one fob, and tore a button off the rubber pad. So I bought 2 new shells and pads. Upon disassembly I noticed the board itself has 4 buttons on it. Which surprised me, that both boards are 4 button, but only 3 button shells. So my question is, what would that 4th button do?
![IMG_20161024_101144135_zps46etayiz.jpg IMG_20161024_101144135_zps46etayiz.jpg](https://www.tahoeyukonforum.com/data/attachments/169/169323-639e2713e25cca60e77cff0b458ac34d.jpg)
![IMG_20161024_101210966_zpsjcpdjbts_edit_1477322601485_zpsotirztt1.jpg IMG_20161024_101210966_zpsjcpdjbts_edit_1477322601485_zpsotirztt1.jpg](https://www.tahoeyukonforum.com/data/attachments/169/169324-564315d057a33302dcfc65575884fc54.jpg)
![IMG_20161024_101144135_zps46etayiz.jpg IMG_20161024_101144135_zps46etayiz.jpg](https://www.tahoeyukonforum.com/data/attachments/169/169323-639e2713e25cca60e77cff0b458ac34d.jpg)
![IMG_20161024_101210966_zpsjcpdjbts_edit_1477322601485_zpsotirztt1.jpg IMG_20161024_101210966_zpsjcpdjbts_edit_1477322601485_zpsotirztt1.jpg](https://www.tahoeyukonforum.com/data/attachments/169/169324-564315d057a33302dcfc65575884fc54.jpg)