As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2705, THE CREW REPORTED A CAPTAINS HEADING FLAG ON CLIMB. THE AIRCRAFT RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NUMBER 1 AHRS COMPUTER, OPERATIONALLY TESTED WITH NO DEFECTS. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.