What was found
DURING THE FIRST STEP OF THE POWER ON CHECKLIST, EMERGENCY LIGHTS DO NOT ILLUMINATE WITH THE SWITCH PLACED IN "ARM" (NO DC POWER ON). LIGHTS DO WORK IN THE "ON" POSITION. WE PERFORMED THE "EMERGENCY LIGHTS FAIL PREFLIGHT TEST" CHECKLIST VIA MAINTANENCE'S INSTRUCTIONS AND RECHECKED THE LIGHTS TWICE AFTER TWO 30 MINUTE CHARGING PERIODS FOR A TOTAL OF 60 MINUTES. AFTER BOTH CHARGING PERIODS THE LIGHTS STILL FAILED TO ILLUMINATE IN THE "ARM" POSITION. CORRECTIVE ACTION: REPLACED FUSE. OPS CHECK GOOD. IAW CE·680A AMM 33-50-00