See Controls and Indicators → Inner Fairing Cap Rocker Switches: FLHTCUSE3 → Switch Indicators: FLHTCUSE3. Use the auxiliary lamp switch (1) to turn ON the auxiliary lamps as required.

NOTE

The auxiliary lamp switch (SPOT) is on the left side of the ignition/headlamp key switch on fairing cap.
The auxiliary lamps (SPOT) do not work when the headlamp is on high beam.