Ac8257 Firmware New Site

This is the most critical step. Downloading the wrong firmware will your unit (no boot, black screen). To avoid this, collect this information from your head unit's Settings > About Device or System Info :

Plug the USB into the head unit's 4-pin or 6-pin USB port. Trigger the Update: ac8257 firmware new

: Most AC8257 units use the YT5760B/D or YT7260D/L boards developed by Xyauto . This is the most critical step