TM 11-6720-239-35
TROUBLESHOOTING
Section 1.
GENERAL TROUBLESHOOTING INFORMATION
isolated by sight, touch, or hearing. The majority
2-1. General Instructions
of faults, however, must be isolated by detailed
a. Troubleshooting at DS, GS, and depot
electrical, mechanical, and optical checks.
maintenance levels include all the techniques out-
b. Sectionalization Check. After the trouble has
lined for organizational maintenance and any spe-
been sectionalized, make a general operational test
cial or additional techniques required to isolate a
of the suspected assembly. The general opera-
defective part. The DS, GS, and depot mainte-
tional test serves as a check of the sectionalizing
nance procedures are not complete in themselves
test.
but supplement the procedures described in opera-
(1) Visual inspection. The purpose of visual
tor and organizational maintenance. The system-
inspection is to locate faults without testing or
atic troubleshooting procedure, which begins with
measuring circuits or components. All visual signs
the operational and sectionalization checks per-
should be analyzed to help localize the fault to a
formed at an organizational level, must be com-
particular subchassis, stage, or unit. Mechanical
pleted by further localizing and isolating tech-
faults are most often localized through visual
niques. Paragraphs 2-5, 2-6, and 2-7 of this
inspection.
chapted provide unit troubleshooting procedures
which must be performed at the DS, GS and depot
c. Localization. These tests listed below will aid
maintenance levels.
in localizing the trouble. First, localize the trouble
to a section or unit. Then isolate the trouble
b. Troubleshooting may be performed while the
within that section or unit by electrical, mechani-
camera is fully assembled or, if necessary, after
cal, or optical checks as required. Use the follow-
the assemblies have been removed. When trouble
ing methods of trouble localization:
occurs, certain observations and operational
(1) Troubleshooting charts. The trouble
checks can be made that will help to determine the
symptoms listed in these charts will act as a guide
source of the trouble. When troubleshooting is
in isolating the trouble in the camera component.
performed while the camera is fully assembled, it
(2) Optical tests. Optical testing procedures
is usually done at the organizational level (TM
will aid in localizing troubles within the optical
11672023912). Troubleshooting at the DS, GS,
system.
and depot levels is usually done with the assem-
blies removed. Paragraphs 23 and 24 describe
d. Isolation.
the systematic procedures to be followed in order
(1) lntermittent troubles. In all tests, the
to isolate the cause of the trouble and correct the
possibility of intermittent troubles should not be
fault.
overlooked. If present, this type of trouble often
may be made evident by gentle tapping or jarring
the equipment. Check the wiring in the camera set
Procedures
for damage and/or loose connections.
(2) Optical troubles. Troubles in optical sys-
a. General. The first step in servicing a defec-
tems can usually be located by visually inspecting
tive camera set is to sectionalize the fault. Sec-
the equipment following step-by-step testing pro-
tionalization means tracing the fault to the major
cedure. Perform the checks (2-5 b ) and compare
assembly. Localization means tracing the fault to
the results obtained with the normal.
the defective subassembly. The third step, isola-
tion, means tracing the fault to the defective part.
Some faults, such as poor shutter response, or
binding of mechanical subassemblies, can often be
a. General. The troubleshooting charts list the
