TROUBLESHOOTING THE M998 ELECT SYST. - OD1617 - LESSON 1/TASK 1
(14) Slave Receptacle.
A slave receptacle located on the front
side of the battery box provides for inter-vehicle cable-starting.
The slave receptacle is compatible with all NATO vehicles.
(15) Glow Plugs.
those of the HMMWV, require a preheating glow plug which extends into
the prechamber to aid in starting the engine when cold. These plugs
are located in each cylinder head below the injector nozzle.
the RUN/START switch is placed in the RUN position, the glow plugs
are energized and air in the prechamber is heated to approximately
1400 F. In 0 F weather, the glow plugs will preheat the prechamber
in six seconds; the engine should then start easily.
(16) Glow Plug Controller.
The glow plugs in the HMMWV are
The controller, located
in the coolant outlet manifold, is a thermal model of the glow plugs
and turns the glow plugs on and off by monitoring engine coolant
. At the unit level only one piece of test equipment
is used to troubleshoot the electrical system; that piece is the
In the paragraphs that follow, we will discuss the
AN/PSM-45 is the most commonly found multimeter in the automotive
unit maintenance number 1 and 2 common tool sets. It is of military
design and is an important and useful piece of test equipment.
can be used to make voltage, resistance, and continuity checks on the
electrical system of the HMMWV.
It is assumed that the student is familiar with the care and
usage of the multimeter.
Therefore, this information will not be
However, additional information concerning the