ARMY TM 9-2815-256-24 AIR FORCE TO 38G1-96-2 MARINE CORPS TM 2815-24/5 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, 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  publications  (i.    e.    , DMWR).  Overhaul in 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 measurements (hours, miles, etc.  ) considered in classifying Army equipment and 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. b. Column  2  Component/Assembly.    Column  2  contains  the  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 2. (For detailed explanation of these functions, see paragraph B-2.  ) 1 Service Inspect, test, service, adjust, aline, 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.  , identification as maintenance significant). 4 Actions Welding, grinding, riveting, straightening, facing, machining, and/or resurfacing. B-2