I own a 2001 s500. dash reads no cd changer. radio or tape doesn''t play then either. seems to come back when it wants. Funny thing is, over the winter it seemed like it needed to warm up first. Now it happens all the time. Any fixes out there. CD changer was replaced last May.
Already Tried: I just keep turning it off and back on till it comes back
You not going to like this answer but, you need a scan tool that can talk to the D2B ring in that car via Command (radio) The Amp, telephone pse, VAD and a few other fiber optic components can cause this along with Command and the steering wheel buttons on the right side.
25 years on MB, diagnostic tech and trainer.