How to start channel scan

I have a 1992 27" Mitsubishi color tv which works properly in all respects. It has been run through a cable box it's entire life. I have recently moved it elsewhere in the house, without a cable box. I'm trying to find out how to start the channel scan feature to allow it to receive channels above 12 or so. The remote has been lost for years, so am using an aftermarket universal control. The tv is a model CS2610RC serial 054901. With the universal control, I cannot access the setup menu.