Figure 2-56.(A) Single-contact bulb; (B) Double-contact
Figure 2-58.Dash-mounted headlight switch.
lamp is also whiter than a conventional lamp, which
increases lighting ability.
The headlights are sealed beam lamps (fig. 2-57)
that illuminate the road during nighttime operation.
Headlights consist of a lens, one or two elements, and a
integral reflector. When current flows through the
element, the element gets white hot and glows. The
reflector and lens direct the light forward.
Many modern passenger vehicles use halogen
headlights. A halogen headlight contains a small, inner
halogen lamp surrounded by a conventional sealed
housing. A halogen headlamp increases light output by
25 percent with no increase in current. The halogen
The headlight switch is an ON/OFF switch and
rheostat (variable resistor) in the dash panel (fig. 2-58)
or on the steering column (fig. 2-59). The headlight
switch controls current flow to the lamps of the
headlight system. The rheostat is for adjusting the
brightness of the instrument panel lights.
Military vehicles that are used in tactical situations
are equipped with a headlight switch that is integrated
with the blackout lighting switch (fig. 2-60). An
important feature of this switch is that it reduces the
possibility of accidentally turning on the lights in a
Figure 2-57.A typical sealed beam headlight assembly.