I have had the same. I did read somewhere that it was due to moisture getting in to the display board in the speedo. It cleared up in the spring. If you go out driving in the winter put the heater on full blast!
I am currently trying to reduce the moisture content of the cockpit and see if that stops the numbers disappearing.
I have left the hood up but not tensioned, and the doors and windows shut. In the drivers footwell I have left a large plastic cake box holding a kilo of silica gel granules. By weighing the silica before and after regenerating in the oven I have extracted over 150ml of water so far this year.
1994 +8, BMW Calypso Red.
2002 4/4, 4 seater, BMW Calypso Red.
How do you open the boot?
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