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Instrument cluster brightness stuck on the dimmest setting

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13K views 9 replies 4 participants last post by  veeeight  
#1 ·
I noticed the other day that my instrument cluster screen was looking extremely dim so i tried the little wheel to the right of the steering and it no longer seems to work, the screen stays on the dimmest setting and so does the ambient lighting (that used to change with the screens)
I have had to increase the brightness on the centre screen but it's still not as bright as it used to be so i'm assuming the wheel is the main dimmer for everything?

I've had a quick google and haven't found anything so if anyone has any suggestions it would be much appreciated.
 
#3 ·
Depends if you’re doing it at night or in the day... I’ve also noticed that you can’t change the brightness during the day but you can at night.

It’s weird
You can change the brightness anytime, well at least i used to be able to. It would be of no use whatsoever if you couldn't change the brightness during the day, that's when you need to increase it, especially if it's really sunny outside.
 
#6 ·
Ok so this is still annoying me slightly as I've done a bit of driving this weekend both in the day and at night and here is what's happening.

Day time driving - No lights on, wheel switch is at full but does nothing, instrument screen really dim, centre screen way brighter because i have it set to max.
Night time driving - Lights on, wheel switch at full and screen is as bright as the centre screen. Wheel now works and can dim the instrument screen to how it looks during the day.

Day time driving but entering a dark area - Wheel switch is on full as normal but instrument screen is dim. Enter a dark area and centre screen switches to dark mode, lights come on and instrument cluster brightens up to match the centre but then allows me to dim.

Is this not completely backwards? Surely during the day the instrument cluster screen should be as bright as the centre screen if I've got the wheel switch at full? During the night i would expect to be able to dim the instrument screen like i can but why does it suddenly go brighter when the car detects it's dark?? I appreciate that screens will look brighter at night but because they can be controlled individually, i can clearly see that during the day the instrument cluster will not go anywhere near as bright as the centre screen however, it will at night???
 
#7 ·
They need to just allow users to dim and increase the brightness when and where possible but idk... it seems to me that they’re hiding something... something like overheating screens 👀 this isn’t a new thing from the new a-class, you hear about it all the time on here about users screens switching off mid drive or not turning on at all... obviously in the day time it’s much hotter so I have a theory that they restrict the brightness of the instrument cluster so the screens don’t overheat as frequently
 
#9 ·
Its a strange one becuase like I say, in the day time it's dim but at night it's really bright, it's as if it's backwards. With that being said, it could simply be that it's at its brightest during the day and it won't allow me to dim because that would obviously be dangerous. If it's at its brightness though, I'm not impressed because while I can still see it, it's really not great.

I've got it booked in for the FUP3 update on Friday so I guess I'll see what happens, I will mention it when I drop the car off though.
 
#10 ·
You can check your ambient light sensor for yourself to see if its working. The sensor is shown by the green arrow on the pic below, its in the black bezel in between the 2 displays. You'll need a bright torch to see it.

You have to test this in daylight (the DRLs will be on automatically), engine running.

And slouch down in the driver seat, so that your eyeline is square and at the same level/height as the driver display (as with all LCD's, viewing angles and contrast diminish if you aren't viewing square onto the display)

Put your thumb over the sensor the display should dim after a few seconds.
Shine a bright torch onto the sensor, the display should increase brightness after a few seconds.


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