This bulletin applies to 2019-2021 Mazda3, 2020-2022 CX-30 vehicles. Some vehicles may exhibit symptoms with DTC P05A0:00 (active air shutter and opening angle abnormality/sticking) stored in memory, even though the air shutter appears to be working. This is caused by improper control software of the PCM detecting the DTC immediately without performing the failsafe operation. When the active air shutter detects unusual torque, it is designed to repeat the open/close cycles up to three times as a failsafe to try to remove objects that temporarily disturb shutter movement. The control software of the PCM has been modified. As part of the modification, the software has been updated to use the ambient temperature sensor instead of the intake air temperature sensor to detect a freezing environment. Update PCM software with the latest release.