TM 5-6115-434-12 Table 3-3.  Troubleshooting Malfunction Probable cause Corrective action 12 Excessive oil temperature. a.  Low oil supply a.  Check oil tank dipstick for proper oil level. b.  Oil cooler cooling air tubes b.  Remove restriction. restricted. c.  Cooling fan failed c.  Replace failed cooling fan (para 3-39). d.  Oil temperature regulator d.  Replace failed oil temper- valve failed. ature regulator valve (para 3-41). e.  Other causes e.  Refer other causes to direct and general support main- tenance personnel. 13 Loss of oil pressure. a.  Low oil supply a.  Check oil tank dipstick for proper oil level. b.  Oil pump pressure relief b.  Replace failed oil pump valve stuck open. pressure relief valve (para 3-31). c.  Oil line kinked or damaged c.  Replace damaged oil line (para 3-29). d.  Oil filter element dirty or d.  Replace oil filter element clogged. (para 3-30). e.  Other causes e.  Refer other causes to direct and general support main- tenance personnel. 14 Load control valve a.  No 400 Hz power a.  Refer to para 2-16b for op- fails to open. eration to deliver 400 Hz electrical power.  Replace failed components as re- quired. b.  Valve solenoid assembly b.  Replace failed solenoid failed. valve assembly. c.  Air pressure regulator im- c.  Refer to para 3-8e(5) for properly adjusted, filter adjustment procedure. contaminated, or failed. Refer to para 3-72 for filter element replacement procedure.  Replace failed air pressure regulator (para 3-71). d.  Load control thermostat d.  Refer to para -8e(2) for improperly adjusted or adjustment procedure. failed. Replace failed load con- trol thermostat (para 3-73). e.  Control air line leaking or e.  Check control air line and damaged. fittings for air leaks. Tighten as required, or re- place damaged line. f.  Load control valve failed f.  Replace failed load control valve (para 3-70). g.  Other causes g.  Refer other causes to direct and general support main- tenance personnel. 15 No 60 Hz ac generator a.  Overload on output a.  Adjust load, reset load con- output (60 Hz trip in- tactor switch (S3) and dicator lamp (DSS) check each phase with 60 illuminated. Hz volt-amp switch (S25). b.  60 Hz load-contactor switch b.  Replace failed 60 Hz lead (S3) failed. contactor switch (para 3-55d). 3-11