What was found
EMERGENCY LIGHTING: UPON LANDING OWNERS INFORMED US THE EMERGENCY LIGHTS HAD BEEN FLASHING FOR APPROXIMATLEY 45 MINUTES. I PLACED THE EMER LT SWITCH TO ALL 3 POSITIONS. ANY TIME THEY WERE PLACED IN ARMED OR ON THEY WOULD FLASH LIKE A STROBE. THIS INCLUDES ALL CABIN LIGHTS, AIRSTAIR LIGHTS AND OVER/UNDER WING LIGHTS. ARRIVED AT THE AIRCRAFT, CONNECTED EXTERNAL POWER AND APPLIED POWER TO THE AIRCRAFT. AFTER 90 MINUTES, TURNED ON THE EMERGENCY LIGHTS AND NO FLICKERING WAS NOTED. I TRIED THE LIGHTING IN THE ON POSITION AS WELL AS THE ARMED POSITION NOTING NO FLICKERING AT THE TIME. SHUT DOWN THE GPU & TURNED OFF MAIN BATTERIES & SWITCHED EMERGENCY LIGHTS TO ON IAW AMM 33-52-01-710-801-A. EMERGENCY BATTERY OPS TEST MINUTES NOTING NORMAL OPERATION. CONNECTED A GPU & TURNED ON MAIN BATTERIES & GROUND POWER FOR 2 HOURS TO ENSURE EMERGENCY BATTRERIES WERE CHARGED. PERFORMED THE OPS CHECK OF THE EMERGENCY BATTERIES REFERENCING AMM 33-52-00-710-801-A NOTING NO DEFECTS AT THIS TIME.