Raspberry Pi 4 Model B Full [updated] Schematic -

: The Raspberry Pi 4 is not "open hardware" in the sense that its full PCB design files and schematics are proprietary. Raspberry Pi Forums Available Official Resources

: There are documented community reports regarding missing schematics for specific board revisions (e.g., v1.1 vs. v1.2), which can make troubleshooting hardware-level issues difficult if your board differs from the version in the public PDF. Raspberry Pi 4 Model B Full Schematic