As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LIGHTING: DURING PREFLIGHT, EMER LTS SWITCH TO ON, NO EMERGENCY LIGHTS INTERIOR OR EXTERIOR CAME ON. HOOKED UP POWER CART TO AC AND LET THE EMERGENCY BATTERIES CHARGE UP FOR AN EXTENDED PERIOD OF TIME. PREFORMED OPERATIONAL CHECK OF THE EMERGENCY LIGHTS AND OPS CHECKS GOOD AT THIS TIME. NO FURTHER MX REQUIRED AT THIS TIME. WORK DONE IRW GL-650 AMM 33-51-00. 07JUN2021