2012 300S Screen, Speakers , AC Control all stopped working
 

Hello can anyone please tell me how to fix this issue.
Firstly began with speakers not working anymore (no sound), alongside my screen flickering on and off (turn on for like 3 hours and off for 6). When screen was on. Backup camera wouldn’t work. Now everything stopped working. Radio, Screen, AC Controls. What do i do to fix this ASAP.