As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GRU - AFTER AIRCRAFT TOWED TO THE REMOTE AREA, EMERGENCY LIGHT ILLUMINATED. UNABLE TO TURN OFF. FOUND FORWARD FLIGHT ATTENDANT PANEL P21 EMERGENCY LIGHT SWITCH OUT OF NORMAL CONFIGURATION. SELECTED EMERGENCY LIGHT TO NORMAL. CHARGED EMERGENCY LIGHT POWER PACKS. SYSTEM GROUND CHECKED NORMAL OPERATION.