TM 9-4120-408-14
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test, measuring,
and diagnostic equipment used in precision measurement. Consists of comparisons of two instruments, one of
which is a certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the
instrument being compared.
g. Remove/Install . To remove and install the same item when required to perform service or other maintenance
functions. Install may be the act of emplacing, seating, or fixing into position a spare, repair part, or module
(component or assembly) in a manner to allow the proper functioning of equipment or a system.
h. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. "Replace" is
authorized by the MAC and assigned maintenance level is shown as the 3d position code of the SMR code.
i. Repair. The application of maintenance services', including fault location/troubleshooting 2, removal/installation,
and disassembly/assembly3 procedures, and maintenance actions4 to identify troubles and restore serviceability
to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly, module
(component or assembly), end item, or system.
j. Overhaul.
That maintenance effort (service/action) prescribed to restore an item to a completely
serviceable/operational condition as required by maintenance standards in appropriate technical publication (i.e.,
DMWR). Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not
normally return an item to like new condition.
k. Rebuild.
Consists of
those services/actions necessary for the restoration of
unserviceable equipment to a
like
new condition in accordance with original manufacturing standards. Rebuild is the highest degree of materiel
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurement (e.g., hour/miles) considered in classifying Army equipment/components.
a. Column 1. Group Number. Column 1 lists functional group code numbers, the purpose of which is to identify
maintenance significant components, assemblies, subassemblies, and modules with the next higher assembly.
b. Column 2, Component/Assembly . Column 2 contains the item names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
c. Column 3. Maintenance Function . Column 3 lists the functions to be performed on the item listed in Column
d. Column 4. Maintenance Level . Column 4 specifies each level of maintenance authorized to perform each
function listed in Column 3, by indicating worktime required (expressed as manhours in whole hours or decimals)
in the appropriate subcolumn. This work-time figure represents the active time
1
Services Inspect, test, service, adjust, align, calibrate, and/or replace.
2
Fault location/troubleshooting The process of investigating and detecting the cause of equipment
malfunctioning; the act of isolating a fault within a system or unit under test (UUT).
3
Disassembly/assembly The step-by-step breakdown (taking apart) of a spare/functional group coded item to the
level of its least component that is assigned an SMR code for the level of maintenance under consideration (i.e.,
identified as maintenance significant).
4
Actions Welding, grinding, riveting, straightening, facing, machining, and/or resurfacing.
B-2