I have only had my Greenline a short while, so I am hoping someone can tell me if what I am seeing is a problem or a feature ?

At night when going down a road with street lights, every time I go under a street light the brightness of the instruments goes up a few levels and as soon as I move away from the light it darkens down again. This means on a long straight urban road at say 50 mph the illumination is going up and down as I pass every streetlight, which is a bit strange and slightly distracting.

I am guessing that its related to the ambient light sensor behind the mirror which looks almost straight up at the streetlights due to the rake of the screen.

Anyone else have this ? Anything I can do.?

The ambient light sensor for the dash and interior lighting is located inside the dash. The sensor on the mirror is for the mirror only, and yes the dash lights do vary when driven under bright streetlights however the variation should be slow and subtle.

The only time this happens in the sharan is when the lights arent on, as the dash is always lilluminated.

Assuming the obvious that the lights are on, and not just the DRLs, then sounds like a computer or sensor fault

I've never particularly noticed the dash lights varying in brightness in mine

_{I had another session of checking it out in the early hours of this morning. Its related to the colour of the street lights. The yellow ones don't cause a reaction, but the ones that give out a very white light make it react almost instantly and noticeably brighten the instruments.}

_{I am now going to look to see if a car coming in the opposite direction has a similar affect.}

I've not noticed that on mine either?

Nor mine and we have the modern white streetlights too.

I tried to review this last night on the way home but couldn't concentrate long enough on the dash whilst not endangering others on the road!

The street lights themselves cause light changes on the instruments - is it not this?

No it isn't, there isn't a subtle increase in brightness either as its a really big change in brightness. What catches my eye, is the central screen suddenly going much brighter as its in my peripheral vision. If it isn't the sensor behind the mirror that triggers the instrument brightness, where is the sensor that does ?

I think it is on either the very edge of the speedo or rev counter (very small round sensor almost invisible) as the FL fabia does this as well if you put interior light on in the car and look at the instruments they should get brighter turn off the light and they dim down. Will check in my dad's Superb when I next go in it to see if it is the same

Fabia00, yes you are correct. I have just been out with a torch and identified the way it works. The sensor is in the speedo somewhere and not the tacho, couldn't see exactly where, but when you shine a small torch at the speedo the instruments go to max brightness in about half a second. Take the torch away and they very slowly dim down over 5 seconds plus. The bit that is distracting my eyes is the speed that they go brighter. Anyway, now I know what is causing it, I now understand. I will mention it to the dealer at the first service to see if the sensitivity can be adjusted.