TM  9-2320-387-24-l REFERENCE   INFORMATION GLOW  PLUGS  CIRCUIT - Refer  to  the  functional    flow   schematic. If the  glow plug  controller    is  shorted   (continuity    from  pin  6  to pin  3)   the  glow   plug  power   relay  will  always   be energized    and   the  glow   plugs  will  always   be drawing    current. BATTERY   CURRENT STEIICE-R   TEST  80 1.  Start  Test   80.  Battery    Current. 2.  Displayed    reading   is in  amps.    The   reading will  be  greater   then   30  amps,   depending    on how   many   accessories    you   have   on. Since   the  glow   plugs   draw current   without    the  glow plug  controller    connected, there   must  be  a short   in the   harness   or  a  stuck relay   in  the   PCB.   If  there were   a  short   in  the harness    directly   to  the glow   plugs,   the   glow   plugs would   have   burned    out long  ago   and  you   wouldn’t be  here.  The  only   other short   in the harness that 3O 4.   so 0 ^{0 l 6} _lo would   make   the   glow GLOW   PLUG   CONTROLLER plugs   turn   on  without    the HARNESS     SCHEMATIC glow   plug  controller installed   would   show. up  as  battery   voltage    at pin  6  of  the  controller’s connector. Replace   PCB   (para.   4-4). Check   the  end   of  the  harness   at  the  PCB,   glow   plugs, etc.,  for  shorts. Repair   whatever    you   can.    If  you   don’t see  anything    wrong,    the  short   must  be  in  the  main body   of  the  harness.    which   means   that  you   have   to replace   the  harness. WARNING Disconnect negative battery cable before    disconnecting and   reconnecting PCB   harness. WARNING There    is  battery     voltage at  the   PCB   at all times.   Failure    to  disconnect battery cable will   result     in  damage    to  equipment or injury     to   personnel. Repair   or  replace   wiring   (para.   4-80). BAITERY CURRENT MULTIMETER 1.  Set  the  voltmeter    to  a  DC  volts   scale   of  about   1 v0n. 2.  Connect   the  BLACK    lead  to  the  battery    side  of the  current   shunt   and   the  RED    lead  to  the  other end  of  the  current   shunt 3.  Current   shunt   voltage    is proportional     to  battery current,    100  millivolts   =  1,000   amps.    To  get current,   multiply   miltiilts x  10. DC  VOLTAGE   O-45 VOLTS STE/lCE-R   TEST  89 1. Connect    RED  clip  to  the  indicated    test  point, BLACK   clip  to  negative    or  ground. 2.  Stan   Test  89.  DC  Votts. 3.  Displayed    reading   is  in  volts. VOLTAGE MULTIMETER 1. Set  the  voltmeter    to  a DC  volts   scale   of  at  least 40  volts. 2.  Connect   the  RED   lead  to  positive    and  the BLACK   lead  to  negative. 3.  Be  sure  to  read  the  correct   scale. 2-297