Blind spot information system
 

Today, whilst driving home the BLIS was on, but the driver's side light kept flashing on/off for no reason. No faults came up though. Any ideas why this happened?

Mine can be set off by low sun shining into the camera lens below the mirror!

Drops of rain falling in front of the lens can also set it off.

^ Mine does the same.

It was constantly on and the flashing on/off was really fast.

Mine has done that. Once switched off overnight it was OK the next day and not been a problem since.

I thought that BLIS used radar mounted in the rear wings'

How dirty is the car ? IIRC in the handbook it mentions a very dirty car can cause issues

'Life Saver Check' is always going to be superior to BLIS

The camera based BLIS systems on the older Volvos struggles in the following conditions:

• Dusk and Dawn
• Rain and shiny roads
• Misty and foggy conditions

Mine often complains, but then resets itself once the conditions improve (and turning car off and on again helps too)

I would agree. I've had the same issues of it flashing around dusk but it's not been one of the sensor being obscured as I got my passenger to clean it whilst moving. after another 60 miles or so it then decided to reset itself and stop flashing, presumably as dusk changed to dark.