As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DURING A TEST OF EMERGENCY LIGHTING SYSTEM, THE AISLE CEILING LIGHT AT ROW 4 DID NOT ILLUMINATE. MAINTENANCE REPLACED CABIN EMERGENCY LIGHT 201WL AT SEAT ROW 4 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 33-51-11.