As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MIA/BOG -ATB - FLT GT063/06 - ENGINE A-LOOP FIRE WARNING FLUCTUATED, B-LOOP READ 4-5 STEADY. ENGINE SHUT DOWN AND FLIGHT RETURNED TO MIA. MIA MAINTENANCE FOUND PRESSURE REGULATOR VALVE AND DUCT LEAKING. REPLACED BOTH PRV, DUCT AND CLAMPS. OPERATIONAL CHECK OF B-LOOP SATISFACTORY. A-LOOP STILL SPIKES AND DEFERRED PER DDPG. AIRCRAFT RELEASED FOR FLIGHT. ADDITIONAL PART INFO: PN 65B94813-2. (X)