As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3794, CREW REPORTED THEY HAD AHARS 1 INOPERATIVE IN FLIGHT AND DESCENDED OUT OF RVSM BECAUSE THAT MESSAGE MAKES THE AUTO PILOT INOPERATIVE. DID NOT HAVE ENOUGH FUEL AT FL280 TO MAKE IT TO DFW REMOVED AIRCRAFT REMOVED FROM SERVICE. REMOVED AND REPLACED NR 1 AHRS UNIT PER AMM 34-21-01. OPERATIONAL CHECKED GOOD ALSO DEFERRED RVSM 34-50 DUE TO REPLACEMENT OF AHRS. AIRCRAFT RETURNED TO SERVICE.