B 747 200 autopilot has VOR/LOC switch position and the next position is ILS if you switch it straight over to ILS before having captured the Localizer it will capture the glideslop and will announce on FMA.
With the switch selected in VOR/LOC the aeroplane will turn on the heading knob until it does capture the localizer, only once the LOC capture has announced do we(our company SOP) select ILS.