zitsky

Middle display went dark. It came back after I turned off power, went outside, locked the car, waited 5 minutes, unlocked car, went inside. Seems like a part or cable problem. Service rep says "software update". How do you do a software update on a display?

Car is currently at dealer. They say there is also a fuel line recall they want to do?

I see electrical problems in my future.... I've only had this car for a few weeks.

Quenthel

My 2018 COMAND had this issue where after a while music playback would stop, be it from a USB stick or over Bluetooth or DAB even. It would work for a bit, especially when I'd have left the car sitting untouched for days, then track changes would need incrementally more time to happen, and in an hour or two at most, it would be dead, Jim.

Went to the dealer, they confirmed the issue and they said they've fixed it with a software update. I can tell something is different because the volume pop up was of a different colour when I got the car back and the problem didn't resurface.

As such, it is not impossible that this might actually solve your problem, though, like in my case and since I come from a software engineering background, I have to wonder wtf and how tf did they develop the software for these had units for it to be causing issues like these. The heck, Mercedes?

zitsky

Thanks. It’s good to know I’m not alone. I’m a software and hardware person. So I tend to not believe anybody. Well let’s see.

Quenthel

Very true. My other thought was that they lied and replaced the head unit, but... since they replaced mine under warranty, I cannot find a proper motive for lying about the software vs the hardware.

Oh, as for minor electrical gremlins, I have had my share of those:
* Twice in the last year, the automatic window closing functionality for the driver's side window would stop working for 10 minutes. I had to keep the button pressed to close it.
* Once, after a long trip the back button on the left side of the steering wheel would stop working. After leaving the car for 20h (I was on a ferry) it would work again. Has never happened again.
* Oil level measurement would not work, for hours. Next day, all is well again.
* Sometimes the middle screen would not turn on automatically when I turn on the engine. I know this happens if you turn off the screen manually before you turn off the car, but that wasn't my case. Had it happen 3 times in the last year (it would turn on immediately when pressing the power button however).
* My favourite. COMAND actually crashing once. Screen frozen, buttons not working. Long press at the COMAND power button and problem solved with a soft reset.
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These have happened very rarely for me to be concerned at all, but they make me wonder what's next. I've used Carly regularly and no serious issues pop up (though I hate carly, 4 years after the S560's release and they still don't support the engine officially).

zitsky

What is Carly???

Tom in Austin

Oil level measurement? Do our cars have something in the display showing oil level?

Quenthel

It's an OBD2 diagnostic that uses a phone app to supposedly get better details on error codes that come up with the car, compared to other off the shelf diagnostic tools. Sometimes this works, others it leaves a few things to be desired (I'm hearing it works great with BMWs however).


Yes, it's under the Service menu, for all cars (at least for the facelift versions, as far as I know) with the exception of the diesel versions if I'm not mistaken, which use a dipstick. In my S560 there no dipstick, only the digital measurement.

Todd in PA

My 2020 560 4Matic center display blacks out occasionally.
After a restart it usually comes back on, but it is definitely worrisome!

zitsky

Could you please explain what you mean by restart? Turn off car? Get out of car? Lock / unlock? Turn off/on did nothing for me. Did you ever take to a dealer?

Quenthel

​​​​​​Hold down the Comand power button for a few seconds until it will restart.

Todd in PA

It seems to reset after I turn the car off and wait a bit.
By accident I might have figured out a way to restart it sooner, but I am not sure.
The last time it was out, I used the button on the console to change the massage function for my seat.(couldn't do it on the display!)
That seemed to reboot the central screen.
I haven't had the opportunity to try it again so I am not sure if that will do the trick or if it was a fluke.
The central screen even blacked out on the test 560 I drove from the dealer!
I try my best to not take the car to the dealer for stuff that's intermittent as they usually screw stuff up or try to upsell me on needless stuff.

zitsky

I know the button for massage. Without a screen how can you know what you’re doing?

Todd in PA

When I hit the seat button, the display came on.
I tried the seat button to see if it would work.

CaliBenzDriver

You did a good job understanding what's going on !

Are you handy with a screwdriver and a 10mm wrench?

Do you want to fix this yourself ?

Can you spare 90mn ?

Is free good enough ...

pull the front carpet to clean the PAINTED GND posts.

Todd in PA

Which side front carpet, why 90 minutes??
Thanks

CaliBenzDriver

start with driver side then passenger footwell area.

90mn is my honest estimation of time necessary.

Battery will need to be disconnected when dealing with GND returns.

Todd in PA

Thanks

zitsky

If this is a grounding issue, can it be fixed by pressing and holding the power button as described above?

CaliBenzDriver

you lost me a bit.. if this is a GND issue, simply fix the bad GND ✅

Resetting the unit can only helps with soft-crashes, not hardware conditions.

zitsky

I read your post but not clear what this is. Do you replace a ground wire? Is this a known issue?

I tried fixing electrical problems on a Volkswagen 30 years ago. I decided I’m no auto mechanic.

CaliBenzDriver

With your above questions, I am not sure how to best help with your next move.

In your particular case, I suggest the best would be to drop your car at a trusted specialist.
---If you picked the right one you'll be golden under $1k,
--- if not it'll be business as usual.


Action oriented ppl will gather clues and quickly act on them to loose that issue.
Knowing the root cause diagnosis renders the fix trivial.
😎

zitsky

Thanks. What I am TRYING to say is that your instructions which I just read again seem to be.

pull up the carpet?

clean or somehow repair ground posts?

That’s it. That’s all.

I would guess most of us NOT ALL will let a mechanic do this.

Would be nice of you care to share how you figured this out.

Thanks for your help.

Just to be clear, this is a vehicle I bought 3 weeks ago. So the people working on it are at the dealership. Where I have taken two other vehicles.

CaliBenzDriver

How to help your trusted dealer expedite fixing this problem for you..?

> Tell 'em your helpful facts: "when my screen blanks out, the seat button brings things back to near normal..."

> You can't instruct a dealer to "I need my front carpet GND looked at"

> Unless you can comme up with a published TSB guided fix, they'll say it is "not applicable to your options" - Some dealers are above standards, a few are clearly below.

Dealers have the latest tools and access to advanced support ressources.
Hopefully they'll get down to it sooner than letter.
Everything depends on who gets assigned to work on your car

> Validation steps:
You may want to evaluate the trunk for the same poor GND condition likely present at the front footwell.
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1 -- Have a quick look around the trunk area behind the liner for the condition of GND Posts...
2 -- The trunk GND's should give you a pretty good example of what the GND messing up your screen look like.

Doubting is a healthy thought process

zitsky

Quenthel,

I'd like to confirm something. You said you can restart COMAND by "long press" the COMAND power button. I think you said press and hold? I ask because I just tried this on a GLC loaner and that did nothing. Are there different software versions for COMAND where some have this "power button reset" and some software versions do not?

zitsky

Dealer says my car is ready. They replaced a fuel line under recall and updated the COMAND software. I told them too late, I just bought a Toyota Corolla. I pick up the car late this afternoon.