Why? Because this unit was strictly sold in Japan for the Japanese market. Pioneer’s English documentation only covered their "AVIC" series meant for North America/Europe (e.g., AVIC-F series, AVIC-X series).
However, there is one massive hurdle for non-Japanese speakers:
I have searched extensively—from Pioneer Japan’s archived support pages to English-language car audio forums. Pioneer Carrozzeria Avic-rz99 English Manual
The Pioneer Carrozzeria AVIC-RZ99 is a beautiful, well-built unit, but it is not beginner-friendly for English speakers. Buy it for its retro JDM aesthetic and excellent audio processing, but accept that the software will always speak Japanese.
If anyone in this thread has a PDF of a translated button map or menu tree, please share it below. It would help keep these classic units on the road. However, there is one massive hurdle for non-Japanese
Here’s a proper informational post suitable for a forum, Facebook group, or blog, regarding the and its English manual. Title: Unlocking the JDM Legend: The Pioneer Carrozzeria AVIC-RZ99 & The Quest for an English Manual
Do not expect to use the built-in GPS navigation for street directions outside of Japan. The maps are locked to Japan, and updating them requires a Japanese SD card and a paid subscription to Pioneer’s "Smart Loop" service (discontinued for this generation). If anyone in this thread has a PDF
If you are reading this, you likely own—or are considering importing—the . This unit is a piece of early 2010s Japanese tech history. As a high-end, Japan Domestic Market (JDM) navi/audio powerhouse, it boasts features that were years ahead of its time: a motorized 7-inch WVGA touchscreen, built-in 3D GPS mapping, DVD/CD playback, SD card slot, USB input, and even built-in digital TV tuners (1Seg/Full Seg).