What was found
AIRCRAFT CREW REPORTED "EMER LT NOT ARM YELLOW CAS: DURING ENGINE START WITH GPU, EMER LT NOT ARM CAS MESSAGE WOULD DISPLAY MOMENTARILY AND EXTINGUISH ON ITS OWN WITHOUT PILOT ACTION. CORRECTIVE ACTION: PERFORMED TROUBLESHOOTING BASED ON THE EMBRAER PHENOM 300 FIM TASK CHAPTER 33-50-00 AND FOUND NR 1 EMERGENCY BATTERY LIGHTS (COCKPIT) FAULTY. PERFORMED REPLACEMENT NR 1 (COCKPIT) EMERGENCY LIGHT BATTERY IN ACCORDANCE WITH PHENOM 300 AMM CHAPTER 33-52-01. PERFORMED OPERATIONAL TEST OF EMERGENCY LIGHT BATTERY IN ACCORDANCE WITH PHENOM 300 AMM CHAPTER 33-52-00. NO DEFECTS NOTED. THIS REPORT COMPLIES WITH FAA 14 CFR PART 135 OPERATOR'S GMM REQUIREMENTS.