What was found
DURING CRUISE FL350 A/P TRIM LT ILLUM. WHILE IN HOLDING TURN. A/P DISENGAGED. A/P TRIM LT. ON THROUGHOUT DESENT. REQUIRED DISENGAGEMENT A/P AND RETRIMMED AGAIN DURING FINAL APPROACH. DURING INITIAL PROBLEM, EGT ON BOTH ENGINES IN REDBAND FOR APPROX. 15 SEC. WHILE AT FL350. DUE TO LOST IN ALT. AND AIRSPEED. WHEN A/P KICKED OFF WHILE HOLDING IN TURN. FOUND ALT TRIM B PHASE C/B POPPED. REPLD R20-12,R20-13NO.2 DFGC AND RUDDER SERVO. BOROSCOPE NR 1 ENG. OK. REPLACED NR 2 ENG DUE TO EGT EXCEDANCE.