MAINTENANCE FUNCTIONS - continued.
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 certified standard of known accuracy, to detect and adjust any discrepancy in
the accuracy of the instrument being compared.
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 an equipment or
Replace. To remove an unserviceable item and install a serviceable counterpart in its place. "Replace" is
authorized by the MAC and is shown as the 3rd position code of the SMR code.
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.
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
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.
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
material maintenance applied to Army equipment. The rebuild operation includes the act of returning to
zero those age measurements (hours/miles, etc.) considered in classifying Army
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 (UTT).
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.