Originally Posted by WA3CUJ

I have had my MBUX screen go completely blank several times, and one time I lost audio but could see the station info on the screen. I found that if I turned the vehicle off and opened and closed the driver's side door, after 5-10 minutes a red triangle would light in my driver's side mirror (the triangle that lights when something is in your blind spot). At that point I can start the vehicle, and everything works ok. I found this by accident while sitting in the vehicle playing games on my phone waiting for my wife to come out of a store.

Originally Posted by DREKNOWSBENZ

I'm documenting these failures was your headunit 548 or 549 if you have Augmented reality the you 4 sure do but if you don't doesn't necessarily mean you don't check your spec sheet should say under the code

Originally Posted by DREKNOWSBENZ

it would be on spec sheet like this
<XXXXXXX>
It be great if you guys can tell me thanks very simple way to know it's can you watch video from usb or online then you have good headunit 548 is trash in my opinion lags and it's obvious the experience is not the same

Originally Posted by mikapen

I finally checked my build. I have U19 AR, and a 548 MBUX. It's been 100% reliable and amazingly quick and responsive. I said "Amazingly quick" because there's absolutely no lag except during a 3 second boot-up. Maybe it doesn't matter whether I have a 548 or 549.

Originally Posted by DREKNOWSBENZ

Hmm that's weird I do not think you can have mbux 548 with Augmented Reality as the plug for it doesn't exist on mbux 548 headunit I've seen tons of them upclose so 🤔 hmm. I bet you have 549 that's why it's quick. Let me ask you can you watch videos on your car screen if so it's a 549 same if Augmented reality is working. I have not seen a 548 with augmented reality and I don't think you.......

Originally Posted by Lucky 777

Yesterday on a road trip, I was using the navigation (which sucks by the way), and stopped to top off the fuel tank. After getting back in and starting the car, the navigation screen was stuck in a blank screen with a prompt that said "Initializing Navigation". There was also no music and when I attempted to switch to audio, it said "Tuner unavailable". I tried waiting it out (10 minutes), also tried turning off and restarting the car. Luckily I had familiarized myself with how to get access to the negative terminal of the battery under the drivers seat and stored a small metric toolkit in the spare tire well. After disconnecting the battery for a few minutes and reconnecting it, everything came back to life. It even resumed navigation and the XM channel I was listening to. After an initial bad experience with this car, I was beginning to really enjoy it. My confidence in the overall reliability and build quality of this car is in the toilet. It's my first Mercedes and will likely be my last. I should change my screen name from Lucky 777 to Unlucky 350.