I reckon it's damp and lower temperatures. Once we've been moving a while, brightness returns to normal.

My SL does similar although it takes longer to get to full brightness.

Fattys. and Mercedes are idiosyncratic, as we all know. 2017 5.0 Autobiography Supercharged
2005 Merc SL350
2005 Disco HSE 2.7 oil burner

I wish mine would stay dim (not that I have this dim at start problem...for now!) - far too bright at night to have it on - very distracting!.

Currently thinking of some window tinting film to dim it a bit as already at the lowest setting the car will let me have!  Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

the dash light brightness control will dim it a little or you can switch of the screen via voice control or the 'red x' icon..

i gather you have the menu brightness to its minimum level.. ... - .- -.




Y. O. L. O.
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Yep Stan, all at minimum values and still too bright so I'll try a bit of window film and see if it affects the touch screen behaviour. Bish.

2005 110 TD5 CSW
2011 TDV8 Vogue SE (gone)

Mine is Dim sometimes too and a yellow brown hue to the display background but gets to normal brightness as It warms up. Didn't think anything of it until now  2007 Vogue TDV8 in Zermatt Silver with Charcoal