What was found
FLT 4568 - DURING CRUISE FROM YOW-ATL, THE CREW RECEIVED A NR 2 IDG CAUTION MESSAGE, ACCOMPANIED BY AN AMBER IDG BOX ON THE ELECTRIC SYNOPTIC PAGE. THE CREW COMPLIED WITH THE QRH AND THE NR 2 IDG DISCONNECT FAILED TO FUNCTION. AN APU OIL TEMP LIGHT ILLUMINATED, THE QRH WAS COMPLIED WITH AND APU OPERATION WAS CONSIDERED ESSENTIAL BECAUSE NR 2 IDG WAS ALREADY OFFLINE. THE AIRCRAFT DIVERTED TO ROA, WHERE IT LANDED SAFELY. MAINTENANCE REMOVED AND REPLACED THE NR 2 IDG AND THE APU OIL COOLER. OPERATIONAL CHECKS GOOD. AIRCRAFT OK FOR SERVICE. (M)