What was found
THE AIRCRAFT RETURNED TO THE FIELD DUE TO THE CAPTAINS SIDE PFD BLINKS OFF INTERMITTENTLY, YAW DAMP 1 INOP MESSAGE INTERMITTENT AND CAPTAIN AND F/O'S HDG SPLIT EFIS COMP MON. MAINTENANCE REPLACED THE ENVIRO CONTROL CARD.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
THE AIRCRAFT RETURNED TO THE FIELD DUE TO THE CAPTAINS SIDE PFD BLINKS OFF INTERMITTENTLY, YAW DAMP 1 INOP MESSAGE INTERMITTENT AND CAPTAIN AND F/O'S HDG SPLIT EFIS COMP MON. MAINTENANCE REPLACED THE ENVIRO CONTROL CARD.