TM  9-2520-272-34&P   CHAPTER   2 TROUBLESHOOTING     PROCEDURES OVERVIEW Troubleshooting   is   a   logical,   systematic   search   for   the   cause(s)   of   malfunction(s).   Direct Support   troubleshooting   of   the   transmission   can   only   be   performed   with   the   transmission installed  in  the  vehicle. NOTE When   troubleshooting   is   performed   with   the   transmission   in   a   vehicle,   the information   in   this   manual   will   be   used   in   conjunction   with   the   information contained   in   the   applicable   -   20   level   vehicle   manual. The   purpose   of   troubleshooting   is   to   establish   the   nature   and   extent   of   repair   required   to   return the   transmission   to   serviceable   condition.   Thorough   troubleshooting   before   the   transmission   is removed   from   the   vehicle   may   reveal   malfunctions   external   to   the   transmission.   Correction   of such   external   malfunctions   may   prevent   the   unnecessary   effort   of   removing   the   transmission. Troubleshooting   by   a   Direct   Support   shop   is   necessary   to   verify   the   diagnosis   made   before   the transmission   was   removed.   Such   troubleshooting   may   be   the   only   means   of   uncovering   all defects   in   a   transmission   received   in   an   unserviceable   condition   from   another   activity. Troubleshooting   may   be   necessary   to   determine   the   cause   when   a   repaired   transmission   fails   to perform  properly.   Paragraph TitIe Page 2-1 2-2 2-3 2-4 2-5 2-6 Preliminary   Inspection Malfunction,   Test   or   Inspection,   and   Corrective   Action Symptom   Index Malfunction,   Test   or   Inspection,   and   Corrective   Action   Procedure Solenoid    Testing    Procedures Pressure    Checking    Procedures 2-1.   PRELIMINARY   INSPECTION 2-1 2-2 2-2 2-3 2-15 2-17 CAUTION Maintenance   personnel   must   have   a   thorough   knowledge   of   vehicle   operation before  attempting  to  troubleshoot  an  installed  transmission.  The  purpose  and  use of   all   operator   controls   must   be   thoroughly   understood.   Refer   to   the   technical manual    for    the    vehicle,    TM9-1450-300-10    (M730A2    vehicle)    or TM9-2350-277-10     (M113A3     vehicle),     for     all     procedures     concerning     the     operation of   the   vehicle Verification   of   all   preliminary   checks   at   crew   and   organization   level   should   be   made. If  preliminary  troubleshooting  of  the  vehicle  is  not  conclusive,  refer  to.  Organizational  manual TM9-1450-300-20 (M730A2 vehicle) or TM9-2350-277-20 (M113A3 vehicle) for preliminary inspections Para.  2-1 2-1