Unsupported Firmware Stops ScreenTune Before the Prompt

ScreenTune changed nothing. Before it shows a prompt, the installer compares the CMU’s firmware with the v74.00.324 build ScreenTune supports. When they differ, it exits with no SCREENTUNE prompt, no message, and no screentune.log on the USB.

Photograph Settings → System → About, including OS Version and Region, then use the table below. Check your firmware version shows the screen and a second method for a frozen menu.

Choose the next step from the OS Version shown

OS Version shown	Next step
74.00.324A (North America) or 74.00.324 with a region code such as EU N, 4A N, or JP M	The firmware is probably not the cause. Rebuild the USB from a fresh download and work through no prompt appears. If the version changed since you ordered, see after a firmware update.
74.00.331	Not supported. See systems ScreenTune does not support yet. Do not downgrade without a support review.
An older build, such as 55, 56, 59, 70, or an earlier 74	Contact support before updating. The supported path is region-correct Mazda firmware only, described in get to v74.
A Gen 7 or newer Mazda Connect system	Not compatible, and no firmware update changes that. See systems ScreenTune does not support yet.

Use region-correct firmware only

Install only the Mazda firmware package for your car’s region. A mismatched package or an interrupted update can leave the CMU unable to boot. Firmware recovery covers an update that stalls.

The version changed after a dealer visit

A dealer visit, a Mazda update, or a replacement CMU can change the firmware after you ordered. Follow after a firmware update before you reuse the USB.