TM 9-2330-388-14
SECTION IV. UNIT TROUBLESHOOTING
GENERAL TROUBLESHOOTING INSTRUCTIONS
(e)
Before starting the written procedure, do a brief,
4-7.
General
but thorough inspection of the system/subsystems you
are dealing with. Look for obvious damage or indications
NOTE
of problems, such as burned or charred wires or paint,
broken wires, or loose or missing hardware. Next,
Before doing any troubleshooting, make sure
starting with block A, perform the checks in the order
you have performed all the PMCS that
given, then answer the question that follows with either a
address the problem area or system.
"YES" or a "NO". Follow the "YES" or "NO" path to the
next block, and so on, until the problem is either fixed or
(a)
This section contains troubleshooting information
referred to support maintenance for correction. Follow-
for locating and correcting the troubles that may develop
on maintenance is listed at the end of the task, if needed.
when operating the semitrailer. Unit Troubleshooting
A fault is considered corrected only when the end item
Fault Symptom Index follows the general instructions as
has been repaired and is returned to a a fully mission
listed at the beginning of Section V. Fault symptoms are
capable condition.
listed by SYSTEM, a FAULT NUMBER, and a FAULT
SYMPTOM. Under FAULT SYMPTOM you will find a
(f)
This manual cannot list all malfunctions that may
brief description, such as "Grabbing Brakes", or a brief
occur, nor all possible tests, inspections, or corrective
description, followed by additional, specific information,
actions. If a malfunction is not listed or corrected by the
such as, " Low Oil Pressure Indicator Light Fails To Light
information given, notify your supervisor.
(Engine Starts Normally)."
(g)
The auxiliary engine on the potable water tanker
(b)
Each malfunction for a component or system is
is directly coupled to the water pump, and, therefore,
followed by an initial setup block that lists tools, supplies,
turns at the same speed as the engine does, at all times.
or additional personnel needed, plus a list of equipment
When performing any test that requires the water tanker
conditions. The equipment condition list will tell you
engine to be running, water must flow through the pump
things you need to do before performing the actual
to prevent damage to water pump, food grade seals, Fig,
troubleshooting procedure.
4-1. Make sure tank contains at least 300 to 500 gallons
of potable water. Connect one end of a hose to the main
(c)
Before you begin any troubleshooting you are
discharge valve outlet, and the other end to the side
required to review the warning summary pages in the
discharge valve outlet. Open emergency and main
front of this book and heed all warnings related to the
discharge valves before starting engine for testing. (See
area you are going to work on. In addition to the
following illustration.) This will allow water to circulate
warnings on the summary pages, other WARNING,
through the water pump in a closed loop, which will
CAUTION, and NOTE entries will follow the initial setup
provide the needed lubricant for the water pump seals.
block, but will precede the step to which they apply, and
are to be considered part of the task.
(h)
When troubleshooting the electrical system,
before you make any continuity checks with your meter,
(d)
The initial setup block is followed by a list of
you must disconnect the negative (-) battery cable from
checks (tests or inspections), in the form of a branching
the battery, and set it aside. Since you must test the
logic tree that will help you determine corrective actions
engine at times during the course of performing your
to take. In many cases, illustrations and diagrams have
checks, you could disconnect and reconnect the battery
been added to further assist you isolating and correcting
a number of times. This is a safety requirement and
the fault.
shall be followed at all times.
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