As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYS - COPILOTS HSI SCREEN TURNED RED THEN BLACK ON BACKGROUND DURING APPROACH AND THEN BACKGROUND TURNED BLUE ON THE GROUND. AFTER ENG SHUTDOWN RETURN TO NORMAL. PERFORMED OPS TEST AMM 34-22-04-864-004 COMPARED BOTH SIDES. ALL CHKD OK. ACFT OK FOR SERVICE.