Buttons on Saratoga II TC Yoke?

[SaratogaPilot]

Hello. New forum member here. I've just acquired a 1998 Saratoga II TC. I've figured out everything about the systems except for this rocker button on the pilot yoke. The prior (second) owner never used the button and doesn't know what it does. Any help would be most appreciated. I look forward to being a member here. Thank you. Robert.

 

[reb]

 

[SaratogaPilot]