What was found
NR 2 ENG FIRE DET FAULT LIGHT ILLUM ON CLIMBOUT AND LEVEL OFF AT CRUISE. WHEN LOOPS A & B WERE TESTED NR 2 FIRE HANDLE WOULD NOT ILLUM. SYSTEM CHK OK ON DESCENT. MX FOUND NO EVIDENCE OF FIRE. FIRE DET UNIT WAS REMOVED AND REPLACED, OPS CHK GOOD IAW MM 26-10-00. THE HOLD DOWN LATCHES FOR THE DET UNIT WERE ADJUSTED AND SECURED. NR 2 ENG FIRE LOOP HARNESS RIGHT AFT SIDE FOR ALOOP WAS REMOVED AND REPLACED DUE TO A BAD LUG. THE REMAINING LOOP CONNECTIONS WERE CHECKED FOR DEFECTS AND NONE WERE NOTED. RESISTANCE CHKS OF THE LOOPS WERE WITHIN LIMITS. IN ADDITION, THE FIRE CONTROL PANEL WAS REMOVED AS A PRECAUTIONARY MEASURE. OPS OF NR 2 ENG FIRE DET SYS CHK GOOD.