I am confused as to what you are inquiring.
Do you have SS assigned to an object that the scanner is stopping on, and you do not want it to do that anymore? Press L/O to temporarily disable it (it will revert to scanning that object the next time you turn the scanner off and then on). Or, as you mentioned, to permanently disable that object, press FUNC-->L/O.
Or do you need to know how to stop SS once it begins, as the sole function of the scanner (i.e. not while set as an object in scan mode)? In that case, press SCAN to resume scanning (and exit SS or Search mode).