TROUBLESHOOTING THE HMMWV - OD1616 - LESSON 1/TASK 2
(10) Electric Horn.
A single electric horn is mounted under the
hood, forward facing, near the front of the vehicle.
It is a
standard military 24 Volt horn, activated by a horn button in the hub
of the steering wheel.
(11) Windshield Wiper/Washer.
The HMMWV includes a windshield
wiper/washer system to maintain a clear field of vision through the
windshield. This system consists of a two-speed electric motor, two
wiper blades, blade linkage, washer reservoir, two washer jets,
connecting hoses, and a motor.
The motor is located inside the
vehicle at the top of the windshield and drives the blade linkage
inside the windshield header.
Dual ten inch blades are actuated by
the linkage and pivot from the top of the windshield frame.
blades operate in unison and return to a PARK position at the right
side of the "wipe pattern" when the wiper switch is turned off.
Windshield washing is accomplished through two jets on the cowl below
the windshield. The fluid is contained in a reservoir located in the
Always use an approved washing solution or
water; NEVER engine anti-freeze.
(12) Heater, Defroster, and Ventilation Mechanisms.
defroster, and ventilation mechanisms usually are combined into one
unit to comprise a complete system.
The unit, which is called a
heater unit, consists of a chambered box containing a heater core and
control doors to allow the operator to select the desired mode of
operation. The outside of the box contains openings for outside air
intake, so that fresh air can be recirculated. The box also has an
interior air intake, so that inside air can be recirculated;
defroster outlets, so that forced air can be provided to clear the
windshield; heater outlets, so that heated air can be provided,
usually at floor level; and, ventilation outlets so that air can be
forced into the passenger compartment at instrument panel level. An
electric blower motor also is combined with this unit to provide air
(a) Heater Core.
The main component of the HMMWV's heater
system is the heater core.
The heater core is the component that
transfers heat from the engine coolant to the passenger compartment.
Its construction is similar to that of a radiator, except it is on a