As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS AVNCS VENT/ AVNCS VALVE PRESSURIZATION FAILED- CABIN WENT TO 12000 AT 16000 MSL. MAINTENANCE REMOVED AND REPLACED SKIN AIR OUTLET VALVE IAW AMM 21-26-53, OPS CHECK OK. REMOVED AND REPLACED DAMAGED AVIONICS VENTING DUCT SECTION IAW AMM 21-26-00. ACCOMPLISHED PRESSURIZATION TEST IAW 05-53-00-780-001-A01. NO PRESSURE LEAKS NOTED AT THIS TIME. (SEE SDR # AALA201912249002)