Cab Air Conditioner/Heater Vents; Engine Cold Weather Starting Aid Switch; Rotating Beacon Light Switch; Heated Mirror Switch - Komatsu 730E Operation & Maintenance Manual

Operation - Section 32
Page 32-14

Cab Air Conditioner/Heater Vents

Cab air conditioner/heater vents (7, Figure 32-10) are
spherically mounted and may be directed by the oper-
ator to provide the most comfortable cabin air flow.
Engine Cold Weather Starting
Aid Switch
Optional engine cold weather
starting aid switch (8, Figure
32-10) is spring-loaded to the
OFF position. Use only when
the ambient temperature is
below 10°C (50°F). When the switch is held in the
ON position, ether is injected into the engine intake
manifold to aid the engine starting in cold weather.
For additional information, refer to Section 30, Oper-
ating Instructions - Engine Start-Up.

Rotating Beacon Light Switch

Press rotating beacon
switch (9, Figure 32-10) to the
ON position to activate the rotat-
ing beacon. This is an optional
feature.

Heated Mirror Switch

Press heated mirror switch (10,
Figure 32-10) to activate the heat-
ing element in the mirrors. This is
an optional feature.
Leakage Test Switch (Trolley Option Only)
Leakage current test switch (11) provides a means
for testing the current leakage relay circuitry of the
trolley system. This circuitry is designed to react to
short circuits between the trolley assist propulsion
system and the truck chassis.
This test must be performed before operating the
truck. Starting with the master control switch in the
DIESEL position, this leakage current test switch
must be held in the ON position for four seconds. If
the system is operating correctly, the trolley fault indi-
cator lamp will turn on. If the light does not turn on,
notify maintenance personnel. The truck can still be
operated in the diesel mode.
To reset, after the trolley fault indicator lamp turns on,
move the master control switch to the trolley position
for a minimum of one second, and then back to the
DIESEL position.
light
Operator Cab and Controls

Wheel Brake Lock Switch

Wheel brake lock switch (12, Figure 32-
10) must only be used when the engine
is on. Use this function during dumping
and loading. When approaching the
shovel or dump area, stop the truck using the service
brake pedal. When the truck is completely stopped
and in the loading position, apply the brake lock by
pressing the rocker switch toward the ON symbol. To
release, press the rocker switch toward the OFF
symbol.
Use the brake lock at the shovel and the dump to
hold the truck in position.
DO NOT use the brake lock to stop the truck,
unless the foot-operated treadle valve does not
work. Use of this switch applies the rear service
brakes with unmodulated pressure!
DO NOT use the brake lock for parking. When the
engine is stopped, hydraulic pressure will dissi-
pate, allowing the brakes to release!

Parking Brake Switch

Parking brake switch (13, Figure 32-10)
is spring-applied
released. It is designed to hold the truck
stationary when the engine is shut off
and the key switch is turned OFF. The truck must be
completely stopped before applying the parking
brake. To apply the parking brake, press the rocker
switch toward the ON symbol. To release the parking
brake, press the rocker switch toward the OFF sym-
bol. When the key switch is ON and the parking
brake switch is applied, parking brake indicator light
(A3, overhead panel) will be illuminated.
NOTE: DO NOT use the parking brake at the shovel
or dump. With the key switch ON and the engine on,
sudden shock caused by loading or dumping could
cause the system's motion sensor to release the park
brake.
OM3241
and hydraulically