What was found
THE APU AUTO SHUT DOWN INFLIGHT AND THE HIGH OIL TEMP LIGHT ILLUMINATED. ALSO, THE NR 2 FIRE BOTTLE LOW AGENT LIGHT ILLUMINATED. THE AIRCRAFT LANDED AT EWR WITHOUT INCIDENT. MAINTENANCE FOUND NR 2 FIRE BOTTLE APU SQUIB BLOWN. THE APU WAS PLACARDED INOPERATIVE. THE NR 2 FIRE BOTTLE WAS REMOVED AND REPLACED. THE NR 2 FIRE BOTTLE APU SQUIB WAS REMOVED AND REPLACED. THE APU PLACARD WAS REMOVED, A TEST OF THE FIRE DETECTION SYSTEM WAS PERFORMED AND OPERATION CHECKED GOOD. *S/D* THE APU CONTINUED TO HAVE A HISTORY OF THE OIL TEMP HIGH LIGHT ILLUMINATING. THE APU FUEL CONTROL UNIT AND TEMP SENSOR WERE REPLACED. THE APU WAS RUN AND OPERATION CHECKED GOOD.