TM 9-2320-211-20
2-157. Dimmer Switch
(2) Position the switch on the back side of the
instrument panel with the switch body extending
a. Removal.
through the hole in the panel, and install the tooth
(1) From inside the cab, remove the two
type lockwasher and hexagon nut on the switch
screws securing the dimmer switch (22, fig. 2-163)
body. Tighten the nut.
to the underside of the toeboard.
(3) Install the switch lever (16, fig. 2-161) on
(2) Disconnect the three bayonet type con-
the switch shaft, and secure it with the screw.
nectors on the switch cables, and remove the switch
(4) Connect the battery ground cable (para 2-
from the vehicle.
134).
b. Installation.
c. Testing. Disconnect all terminals. Connect
(1) Position the dimmer switch (22, fig. 2-
one terminal of the test light or the buzzer to the
161) on the under side of the toeboard, and secure
battery cable and test for continuity of all ter-
it with two screws from inside the cab.
minals.
(2) Connect the three bayonet type connectors
on the switch cables.
2-155. Light Switch
2-158. Stoplight Switch.
a. Removal.
(1) Unscrew the nuts securing the two wiring
a. Removal.
harness plugs to the receptacles on the bottom of
(1) Disconnect the two bayonet type con-
the light switch, at the back side of the instrument
nectors at the top of the stoplight switch.
panel, and pull both harness plugs from the
( 2 ) Unscrew the sleeve nut on the brake
receptacles.
hydraulic line from the elbow at the bottom of the
(2) Remove the four screws from the front of
switch.
the instrument panel, and remove the switch (17,
(3) Remove the two screws and nuts securing
the switch to the inside of the frame left side rail,
and remove the switch from the vehicle.
b. Installation.
b. Installation.
(1) Position the light switch on the back side
of the instrument panel with the electrical recep-
(1) Position the stoplight switch on the inside
tacles pointing down, and the switch housing ex-
of the frame left side rail, and secure it with two
tending through the opening in the instrument
screws and nuts.
panel. Install the four screws, and tighten them.
(2) Position the brake hydraulic line at the
(2) Insert the two wiring harness plugs in the
elbow on the bottom of the switch, and tighten the
receptacles on the bottom of the light switch (17,
sleeve nut on the elbow.
(3) Connect the two bayonet type connectors
on the harness cables to the terminal connectors on
2-156. Horn Button (switch)
top of the switch.
a. Removal.
(4) Bleed
the
brakes
if
(1) While holding the steering wheel
necessary.
stationary, press down on the horn button (21, fig.
2-159. Low Air Pressure Warning Buzzer
release it. Lift the button from the steering wheel
a. Removal.
hub.
(1) Disconnect the terminal connections at the
(2) Remove the contact button cup, spring,
buzzer.
and cap from the center of the steering wheel.
( 2 ) Remove the three screws, lockwashers,
(3) Remove the three screws securing the horn
and nuts securing the buzzer to the back side of the
button plate to the hub. Leave the horn wire in
instrument panel, and remove the buzzer.
position, and remove the plate from the hub.
b. Installation.
b. Installation.
(1) Position the low air pressure warning
(1) Position the horn button plate in the
buzzer on the back side of the instrument panel,
center of the steering wheel hub, and secure it with
and secure it with three screws, lockwashers, and
three screws.
nuts.
(2) Install the contact button cap, spring, and
(2) Connect the low air pressure sending unit
cup on the horn button plate.
cable to the buzzer terminal.
(3) Position the horn button (21, fig. 2-161)
2-160. Circuit Breakers
in the center of the steering wheel hub, press down
a. Removal.
the button, and turn it in either direction until the
(1) Disconnect the two bayonet type con-
button flange is locked in the rubber retainers on
n e c t o r s on the harness cable from the circuit-
the horn button plate. Release the horn button.
breaker terminal connectors.
