AN A-320 CREW EXPERIENCES A FAULTED B LOOP IN THE ACFT'S FIRE WARNING SYS AND THEN A FIRE WARNING WHICH SEEMS TO CLR ITSELF PRIOR TO CHKLIST EXECUTION.

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CLBING THROUGH 9000 FT WE RECEIVED AN ENG 1 'B' LOOP DETECTOR FAULT ON THE ECAM. THIS LASTED APPROX 10 SECONDS THEN CLRED ITSELF. LESS THAN A MIN LATER THE ENG 1 FIRE WARNING ILLUMINATED. WE REQUESTED AND WERE GRANTED CLRNC TO LEVEL OFF AT 11000 FT. ONCE AGAIN THE FAULT CLRED ITSELF AS WE PREPARED TO EXECUTE THE CHKLIST. THE WARNING WAS PRESENT FOR APPROX 15 SECONDS. WE CHKED THE ENG INSTS AND VISUALLY INSPECTED THE ENG. THE ONLY DISCREPANCY NOTED WAS A SLIGHTLY HIGHER NACELLE TEMP ON #1 WITH BLEED PRESSURE 2 PSI LOWER. READINGS WERE: #1 NACELLE 205 DEGS C; BLEED PRESSURE 38 PSI; AND ON #2 170 DEGS C NACELLE TEMP; 40 PSI BLEED PRESSURE. WE CONTINUED ON COURSE AND CONTACTED DISPATCH AND MAINT CTL TO DISCUSS THE PROB. MAINT AND CTL SUSPECTED A SLIGHT BLEED LEAK ON #1 BUT STATED (WITH DISPATCH CONCURRENCE) THAT THE PROB DID NOT WARRANT A DIVERSION. WE ELECTED TO CONTINUE TO DEST WITH NO FURTHER INCIDENTS. UPON ARR WE ENTERED THE DISCREPANCY IN THE ACFT'S LOGBOOK. AFTER FURTHER REFLECTION; IT MIGHT HAVE BEEN MORE PRUDENT TO DIVERT. IT SEEMS THAT WITH THE LEVEL OF COMPUTERIZATION WE NOW HAVE; WE MAY BE LESS LIKELY TO TREAT A WARNING SERIOUSLY BECAUSE WE RECEIVE SO MANY FALSE WARNINGS; IE; WARNINGS THAT APPEAR FOR A SHORT TIME AND THEN CLR THEMSELVES FROM THE COMPUTER; AND OTHERS THAT MAY BE CLRED BY RESETTING THE COMPUTER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR RETURNED CALL WITH THE FOLLOWING INFO. THE A-320 HAS BEEN HAVING A RASH OF FIRE WARNING LOOP FAULTS. HE STATED THAT THIS PARTICULAR ACFT WAS TAKEN OTS AFTER THEY ARRIVED AT THE DEST ARPT. THE MAINT LOG INDICATED THAT MAINT CHANGED BOTH LOOPS IN THE SYS. HE ISN'T CERTAIN THAT THIS WAS THE CAUSE OF THE FIRE WARNING BUT THE ACFT SYS IS DESIGNED TO GIVE A FIRE WARNING WHEN BOTH LOOPS DEVELOP A FAULT. HE WILL INVESTIGATE FURTHER AND ADVISE. HE FURTHER INDICATED THAT HE HAS SEEN MORE EXTREME NACELLE TEMPS THAN IN THIS CASE. HE FELT THERE MIGHT HAVE BEEN A BLEED AIR LEAK IN THIS INCIDENT BUT TO WHAT EXTENT HE WASN'T CERTAIN. HE REITERATED HIS FEELINGS THAT HE SHOULD HAVE DIVERTED BACK TO LAX FOR A MAINT CHK AND CORRECTION. HE AGREED WITH THE ANALYST'S ASSESSMENT THAT HE MAY HAVE BEEN IN CONTINUED FLT TOWARDS DEST ARPT WITHOUT ANY FIRE WARNING SENSING BECAUSE OF FAULTED LOOPS. RPTR MADE A SECOND CALL WITH THE FOLLOWING INFO: HE AGAIN STATED THAT THIS PARTICULAR ACFT HAD BEEN TAKEN OTS AFTER THEY ARRIVED AT THE DEST ARPT. THE ACFT LOG INDICATED THAT MAINT CHANGED BOTH LOOPS IN THE SYS. HE IS NOW CERTAIN THAT THIS WAS THE CAUSE OF THE FIRE WARNING AS THE ACFT SYS IS DESIGNED TO GIVE A FIRE WARNING WHEN BOTH LOOPS DEVELOP A FAULT. HE TALKED WITH OTHER PERSONS NOT IDENTED; AND FOUND ANOTHER CREW THAT HAD EXPERIENCED THE SAME SYMPTOMS OF FAULTED LOOPS AS HE HAD ON THE PREVIOUSLY STATED DATE. THIS CREW HAD THE SAME ACFT 4 DAYS LATER; AFTER THE MAINT HAD BEEN PERFORMED ON IT.