As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A LH ENGINE FIRE WARNING IN FLIGHT WHILE CLIMBING THRU 12,000 FEET.. PULLED THROTTLE TO IDLE AND WARNING STOPPED. CREW DECLARED EMERGENCY AND RETURNED TO TTN. MAINTENANCE PERSONNEL TROUBLESHOT THE DISCREPANCY AND FOUND THE LH ENGINE PRESSURE SHUT OFF VALVE (PRSOV) WAS NOT OPENING TO VENT THE EXCESS BLEED AIR. THERE WAS NO DAMAGE TO THE AIRCRAFT. THE PRSOV WAS REPLACED AND THE DISCREPANCY CORRECTED.