Electrics: D.I.M. goes darker sometimes

[hoggyf]

Hi

On my 2000 V70XC petrol I just noticed at the weekend that the drivers information module was intermittenly going dim then would brighten up again later. It looks a bit like when you put the headlights on in another car and the dash dims down.

Anyone come across this before?? Shoudl I worry??

cheers

[Missing Lincs]

Does this happen when the light levels inside the car change, for instance when there are moving shadows?

[hoggyf]

Not sure really,

It was when I started the car on sunday afternoon, I thought that the display was a bit dim, then after about 20mins driving, it came brighter, then a short while after it darkened, then brighter again.

I've never driven the car in darkness but I notice there are what look like sensors on the interior mirror, will it have auto dimming mirror and correspondingly adjust the display for night time?

[magnus308]

I have noticed the same thing on mine, I drive the same way every morning to work and pass through several darker tunnels and open areas in sunlight and it autoadjust at the same location every day.

[aslan]

Mine has been doing the same thing. I thought it was faulty.

If it goes dim and you adjust the brightness dial a tiny bit, does it becomes all bright again? Is that normal?

[Brendan W]

Mine does the same , generally twilight times. V70 D5 2003

[y2blade]

noticed mine doing it as I drive into the garage with the garage lights off...auto dimming feature I assume

mine doesn't do it willy nilly though so yours may be faulty

[Missing Lincs]

Some degree of auto adjustment is normal, like when you go from light to dark. If the dash brightness as changing without any reason then it could be a fault.
Hoggyf, is it just the brightness of the main instrument cluster (speedo etc) that changes or does everything do the same, centre console etc?
The light sensor on the back of the rear view mirror is for auto dimming of the mirror, this isn't a feature of all models. It should detect when light from headlights behind the car fall on the mirror and adjust accordingly. The sensitivity can be adjusted but this requires special equipment.
I think the sensor for the adjustment of the dash lighting is on the front of the rear view mirror, however not 100% sure on that, perhaps someone else can clarify?

[Symes]

I thought this was a feature, (the sensor on the dash with the alarm led in) the radio display also dims when driving through areas of shadow such as forest roads. Not sure if it can be adjusted but someone might know.