What was found
DURING ROUTINE MAINTENANCE VISIT FOUR RED FLOOR EMERGENCY LIGHTS AT ROW 4 WERE FOUND TO BE INOPERATIVE. ALSO, FORWARD AND AFT LEFT AND RIGHT UPPER SIDEWALL EMERGENCY LIGHTS WERE FOUND TO BE INOPERATIVE. EMERGENCY LIGHTING SYSTEM WAS TROUBLESHOT AND A BURNT WIRE ON A POST CONNECTOR FOR POSITION 500 POWER SUPPLY WAS FOUND. POWER SUPPLY WAS REPLACED AT POSITION 500. ALSO FOUND WAS A BAD DIODE FOR THE RED FLOOR LIGHTS. DIODE WAS REPLACED. ALL EMERGENCY LIGHT BATTERIES WERE REPLACED DURING TROUBLESHOOTING. OPERATIONAL CHECK OF ALL EMERGENCY LIGHTS WAS GOOD. AIRCRAFT RETURNED TO SERVICE.