As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB CABIN ALTITUDE WARNING HORN SOUNDED. CABIN ALTITUDE ABOVE 10000 FT CABIN VSI +500/MIN IN AUTO MODE WITH NO WARNING LIGHTS OR FAILURE OF AUTO MODE SHOWING. CABIN ALTITUDE CONTROLLED WITH MANUAL CONTROL. REPLACED CABIN PRESS CONTROLLER AND CONTROL PANEL PER M/M AND PERFORMED OPERATIONAL TEST AND CABIN LEAK DOWN CHECK NTF.