This is an easy fix – if i’m understanding you – and one I use to wipe pages if a user navigates off halfway through entering information.
phoneui.prePageTransition = function(currentPageId,targetPageId) {
// add custom pre-transition code here
// return false to terminate transition
if (targetPageId == '#m1-ScreenTwo')
{---CODE TO RESET COMBOBOX VALUE---;}
}
-1TC