As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 1001 - MKE-STL - THE CABIN ALT HI ILLUMINATED AND THE CABIN OXYGEN MASKS WERE DEPLOYED. THE CREW MADE AN UNEVENTFUL LANDING IN STL AND CONTACTED MX. OUTSTATION MAINTENANCE PERFORM THE MX FUNCTIONS AND MEL THE PRESSURIZATION. THE AIRCRAFT WAS RETURNED TO SERVICE. MEL WAS CLEARED ON 7/21/00 BY REPLACING THE OUTFLOW VALVE. (M)