2014 300S RB5 Radio Unit Not Functioning
 

Radio unit went out a couple of months ago, all was fine then in the morning it would not come on, radio and navigation screen is also off, none of the controls are working, also noticed the LCD behind steering wheel is now in German.

Checked all fuses - OK
Reconnected battery - LCD behind steering wheel went to English briefly for a few minutes, then switched back to German, no change too radio and navigation screen and controls.

Been driving the car as is for now, in the meantime the radio and navigation screen/controls started working one morning (this happened on 2 occasions), restarted car a few times all seemed ok, next day issues returned, now still no radio or navigation lcd or controls are working.

While car was under warranty dealer replaced the wiring harness for a separate issue I was having at the time, leading me to suspect the wiring but can't prove it...

I am about to buy another radio, my question, could this be a wiring issue somewhere ? or internal radio issue loose or failing component ? Dealer recommends I replace the radio unit but the intermitency puzzles me.

Radio part number/model: P68210554AE

Any thoughts would be appreciated.

i have basically the same issue...my screen went blank/HVAC/radio controls not working.