Garmin GNS 530 Pilot's Manual And Reference page 115

ILS approach is first selected and
automatically placed in the standby field. In
order to fly the final course segment of the ILS
approach, the pilot must place the ILS frequency
in the active frequency field by pressing the
VLOC Flip-flop
appropriate frequency for approach' message
enabled:
1.
outbound and on the initial portion of
the procedure turn.
of the approach from the time the pilot
turns inbound on the procedure turn.
3.
automatic
1.
at any point on the approach prior to
190-00181-00 Rev. G
frequency is
frequency must be active
frequency must be active to
GNS 530(A) Pilot's Guide and Reference
SECTION 6
PROCEDURES
6-33