TM 10-3930-669-20 WARNING Remove all jewelry such as rings, dog tags, bracelets, etc.  If jewelry contacts battery terminal, a direct short may result in instant heating of tools, damage to equipment.  and injury or death to personnel. VOLTAGE TEST (1)   Remove   diode   module   DM1   (Para   7- 33). (2)   Set  multimeter  select  switch  to  VOLTS DC. (3)   Connect  positive  (+)  multimeter  lead  to diode module DM1, terminal 2 cavity. (4)   Connect negative (-) multimeter lead to a known good ground. (5)   Start engine (TM 10-3930-669-10). (a)   If    there    are    not    22    to    24    vdc present,   perform   Step   (6)   and   (7) below    and    repair    wire    33    (see schematic Appendix F). (b)   If  there  are  22  to  24  vdc  present, perform Step (6) below and replace diode  module  DM1  (6)  Shut  down engine. (7)   Install diode module DM1. VOLTAGE TEST (1)   Remove   diode   module   DM2   (Para   7- 33). (2)   Set  multimeter  select  switch  to  VOLTS DC. (3)  Connect  positive  (+)  multimeter  lead  to diode     module     DM2.          terminal     T2 (engages    in    forward)    or    terminal    4 (engages in reverse). (4)   Connect negative (-) multimeter lead to a known good ground. (5)   Set     MAIN     POWER     switch     to     ON position (TM 10-3930-669-10). (6)   Set   engine   switch   to   ignition   position (TM 10-3930-669-10). (a)   If    there    are    not    22    to    24    vdc present,  perform  Steps  (7)  through (9) below and repair wire 39 (forward)  or  wire  40  (reverse)  (see schematic Appendix F). (b)   If  there  are  22  to  24  vdc  present, wire 34 (forward) or wire 40 (reverse)   is   OK.      Do   not   install diode module. (7)   Set engine switch to off position. (8)   Set    MAIN    POWER    switch    to    OFF position. (9)   Install diode module DM2. 2-277