What was found
CABIN EMERG LIGHT: DURING CRUISE WITH EMER LT SWITCH IN ARM POSITION, ALL CABIN EMER LIGHTS BEGAN FLASHING. TURNED EMER LT SWITCH TO OFF POSITION FOR A FEW SECONDS AND TURNED IT BACK TO ARM POSITION. CABIN EMER LIGHTS REMAINED CONTINUOUSLY FLASHING UNTIL SHUT DOWN. // SIGNOFF// USED TC-E50-33-1001, EMBRAER AMM TASK 33-52-01-710-801-A AND AMM TASK 33-52-00-71-801A FOR TROUBLESHOOTING. WHEN EMERGENCY BATTERY 1 WAS DISCONNECTED, LIGHTS FLASHED BRIEFLY. PROCEEDED WITH DISCHARGE/RECHARGE PROCEDURE SPECIFIED FROMTC-E50-33-1001 EMERGENCY BATTERY EXERCISE PROCEDURE. OPS CHECKED ONCE BATTERIES WERE FULLY RECHARGED AND ISSUE WAS NOT PRESENT. (PERFORMED OPERATION TWICE OPS CHECK GOOD, NO FLASHING LIGHTS.