TM   5-3895-360-13 B-2.   MAINTENANCE   FUNCTIONS   (Con’t). (9) (10) (11) Repair.  The  application  of  maintenance  ser- vices, including fault location/troubleshooting, removal/installation,    and    disassembly/as- sembly 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 (component or assembly), end item, or system. Overhaul.  That  maintenance  effort  (service/ action) prescribed to restore an item to a com- pletely  serviceable/operational  condition  as  re- quired   by   maintenance   standards   in appropriate    technical    publications    (i.    e., DMWR), Overhaul is normally the highest de- gree 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  accor- dance with original manufacturing standards. Rebuild is the highest degree of materiel main- tenance  applied  to  Army  equipment.  me  re- build operation includes the act of returning to zero  those  age  measurements  (hours/miles, etc.)   considered   in   classifying   Army   equip- ment/components. B-3. EXPLANATION OF COLUMNS IN THE MAC, SECTION Il. a. b. Column  1,  Group  Number. Column 1 lists func- tional group code numbers, the purpose of which is to  identify  maintenance  significant  components,  as- semblies,  subassemblies,  and  modules  with  the next higher assembly, End item group number shall be “00.” Column  2,  Component/Assembly. Column 2 con- tains the names of components, assemblies, subas- semblies,  and  modules  for  which  maintenance  is authorized. c. d. e. f. Column 3, Maintenance Function. Column 3 lists the functions to be performed on the item listed in Column  2.  (For  a  detailed  explanation  of  these functions,  refer  to  paragraph  B-2.) Column   4,   Maintenance   Level.   Column   4 specifies, by the listing of a  work time figure in the appropriate subcolumn (s), the level of maintenance authorized to perform the function listed in Column 3. This  figure  represents  the  active  time  required  to perform that maintenance function at the indicated level of maintenance. If the number or complexity of the tasks within the listed maintenance function vary at  different  maintenance  levels,  appropriate  work time figures will be shown for each level. The work time figure represents the average time required to restore   an   item   (assembly,   subassembly, component,  module,  end  item,  or  system)  to  a servilceable condition under typical field operating conditions.   This   time   includes   preparation   time (including   any   necessary   disassembiy/assembly time),   troubleshooting/fault   location   time,   and quality assurance/quality control time in addition to the   time   required   to   perform   the   specific   tasks identified for the maintenance functions authorized in  the  Maintenance  Allocation  Chart.  The  symbol designations for the various maintenance Ievels are as follows: C . . . . .  Unit  (Operator  or  Crew) O . . . . .  Unit  Maintenance F . . . . .  Direct Support Maintenance H . . . . .  General Support Maintenance D . . . . .  Depot Maintenance Column  5,  Tools  and  Equipment.  Column  5 specifies,  by  code,  those  common  tool  sets  (not individual   tools)   and   special   tools,   TMDE,   and support   equipment   required   to   perform   the designated function. Column   6,   Remarks.  This  column  shall,  when applicable,   contain   a   letter   code,   in   alphabetic order, which shall be keyed to the remarks contained in Section IV. B-2