As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON ACFT POWERUP, PRESSURIZATION AMBER AUTO FAIL AND GREEN ALT LIGHTS ILLUMINATED ON COCKPIT OVERHEAD. DURING SUBSEQUENT TROUBLESHOOTING NR 2 CABIN PRESSURE CONTROLLER PN 7121-19971-01AC FAILED LRU BITE CHECK. CABIN PRESSURE CONTROLLER WAS REPLACED AND SYS OPERATIONALLY CHECKED NORMAL.