While the manual does not officially endorse hacking, the English translation reveals the hidden "Secret Menu" (holding down the 'Home' + 'Map' buttons for 10 seconds) which allows you to change the DVD region code from Region 2 (Japan) to Region 0 (All regions).
If you need the original Japanese manual (for wiring diagrams, specs, or button functions), use these sources: pioneer carrozzeria avicmrz09 english manual upd link
Archive.org
eBay / Yahoo Auctions Japan
Product: Pioneer Carrozzeria AVIC-MRZ09 Navigation System While the manual does not officially endorse hacking,
The Pioneer Carrozzeria AVIC-MRZ09 is a high-end, double-DIN in-dash navigation and multimedia system. Featuring a motorized 7-inch touchscreen, built-in navigation, and DVD playback, it offers robust audio-visual performance. Archive