As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH BATTERY IN THE OFF POSITION AND EMERGENCY LIGHTS SWITCHED ON, THERE IS NO ILLUMINATION OF THE THREE EMERGENCY EXIT SIGNS SURROUNDING THE MAIN CABIN DOOR. CORRECTIVE ACTION: REMOVED THE FWD EMERGENCY BATTEY PACK AND INSTALLED THE OVERHAULED UNIT IAW CE560XL AMM 33-50-01. OPS CHECK GOOD.