As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING DESCENT PASSING FL360 RED MASTER WARNING AND RED CAS DIFF PRESS ILLUMINATED. DIFF PRESS WAS 9.1 AND WENT AS HIGH AS 9.7. QRH USED AND FL270 DIFF PRESS WENT FROM RED TO GREEN. APU BLEED NOT TRANSFERRED UNTIL ON THE GROUND. CORRECTIVE ACTION: REPLACED CABIN PRESSURIZATION CONTROLLER IAW CL-650 AMM 21-31-13 OPS CHECK GOOD, LEAK CHECK GOOD