What was found
FLIGHT 5675 - RECEIVED EFIS COMP MON CAUTION MESSAGE. ATTEMPTED TO CORRECT, BOTH HSI'S SHOWED RED HEADING FLAG. ATC ADVISED30 DEGREES OFF COURSE. RETURNED TO BOS, LANDED WITHOUT INCIDENT. REPLACED NR 2 AHRS. NO FURTHER DEFECTS.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
FLIGHT 5675 - RECEIVED EFIS COMP MON CAUTION MESSAGE. ATTEMPTED TO CORRECT, BOTH HSI'S SHOWED RED HEADING FLAG. ATC ADVISED30 DEGREES OFF COURSE. RETURNED TO BOS, LANDED WITHOUT INCIDENT. REPLACED NR 2 AHRS. NO FURTHER DEFECTS.