What was found
L GEN DISCONNECT IN FLIGHT. TROUBLESHOT PER FIM 24-20. BITE CHECK OF BPCU SHOWED "SERVICE IDG". " IDG/PMG WIRING" AND "UNDER FREQ TRIP" FOR L GEN SYS INSPECTION OF IDG REVEALED LOW OIL LEVEL AND DPI NOT EXTENDED. CHECKED LINES, TIGHTENED. OIL IN LINE. REMOVED SCAVENGE FILTER AND CHECK FOR CONTAMINATION PER MM 24-11. NO CONTAMINATION FOUND. INSTALLED FILTER PER MM 24-11. DRAIN AND SERVICED IDG PER MM 12-13. RAN ENG AT GATE 75 PERCENT N3 FOR 10 MINS, NO LEAKS. TAXIED A/C OUT, RAN L ENG FOR 30 MIN AT 75 PERCENT N3 EVERY 5 MIN FOR 5 MIN. NO LEAKS NOTED. L IDG OPS NORMAL BPCU BITE CHECK OF LEFT GEN SYS OK.