What was found
AT CRUISE, STAB TRIM LIGHT CAME ON, ELEC SWITCH ON YOKE DID NOT WORK. MANUAL STAB TRIM WORKED. FOLLOWED CHECKLIST, USED MANUAL TRIM, FLAPS 15 DEGREES AND DECLARED EMERGENCY. ON DFCS BITE FOUND A SYS FAULT 22-11177. PERFORMED TASK22-11-934 TEST PASS INTERMITTENT FAULT. ALSO PERFORMED TASK 22-11-81-710-801, AND TASK 27-41-71-700-801. ALL TESTS PASS. INSPECTED STAB TAIL COMPARTMENT. NO DEFECTS NOTED.