As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOTED WAS IN A CLIMB OUT OF TYS WHEN THE PRESSURIZATION ICIAS MESSAGE WENT INOPERATIVE. THE CREW RETURN TO TYS AND MAINT. R & R THE PRESSURE CONTROLLER, OPS CHECK WAS GOOD IAW EMB 145 MM 21-31-00. AIRCRAFT WAS REL. AND NO FURTHER PROBLEMS OCCURED.