Odometer Cluster Button.

[VeYzZii]

This is a pretty weird question, but on the s2000 ap1 dash ''cluster'' (not much of a cluster), toward the bottom right there are to buttons, one is to switch from TRIP A to TRIP B, and holding it will reset the counter, but the button next to it on the left has no effect when i hold it or just press it..??

[3AM]

on overseas models this button changes between kph and mph.

not needed in aus so its just a redundant button.