What was found
ENGINE FIRE LIGHT (DASHBOARD AND FIRE HANDLE) NUMBER 1 ENGINE ILLUMINATED MOMENTARILY INFLIGHT ON APPROACH (APPROX 11,000FT AND 300K), ACCOMPANIED BY FIRE BELL. LIGHT AND BELL WENT OUT, FIRE TEST CHECK OK, ALL ENGINE INDICATIONS NORMAL. APPROXIMATELY 3 MINUTES LATER, NR 1 FIRE LIGHT AND BELL CAME ON AGAIN AND WENT OFF BY ITSELF IN ONE SECOND, FIRE TESTED OK AGAIN, ALL INDICATIONS NORMAL. REMOVED AND REPLACED NR 1 ENGINE FIRE DETECTION ELEMENT PER AMM 26-11-012-01. TESTED FIRE DETECTION SYSTEM PER AMM 26-11-001-0, NO FAULTS NOTED. SYSTEM OPS CKS NORMAL.