B-2. Maintenance Functions. (CONT)
i. Repair. The application of maintenance services1 including fault location/troubleshooting2, 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.
j. Overhaul. The maintenance effort (service/action) prescribed to restore an item to a completely serviceable/
operational condition as required by maintenance standards in appropriate technical publications (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 service/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
measurements (e.g. hours, miles) considered in classifying Army equipment/components.
B-3. Explanation of Columns in the MAC, Section II.
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.
1Services - Inspect, test, service, adjust, align, calibrate, and/or replace.
2Fault 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).
3Disassembly/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).
4Actions - Welding, grinding, riveting, straightening, facing, machining, and/or resurfacing.