ARMY TM 9-2815-254-24 AIR FORCE TO 38G1-94-2 f. g. h. i. j. k. Calibrate.  To  determine  and  cause  corrections  to  be  made  or  to  be  adjusted  on  instruments  or  Test,  Measuring, and Diagnostic Equipment (TMDE) used in precision measurement. Consists of comparisons of two instru- ments,  one  of  which  is  a  certified  standardof  known  accuracy,  to  detect  and  adjust  any  discrepancy  in  the  accu- racy 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 system. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. Replace is autho- rized by the MAC and is shown as the 3rd position code of the SMR code. Repair. The application of maintenance services, including fault location/troubleshooting, removal/installation and disassembly/assembly procedures, and maintenance actions to identify troubles and restore serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly, module (compo- nent 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 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 are to identify maintenance significant components, assemblies, subassemblies, and modules with the next higher assem- bly. End item group number shall be “00”. b. Column 2, Component/Assembly. Column 2 contains the names of components, assemblies, subassemblies, and modules for which maintenance is authorized. B-2