Hi! Got the same problem with both my MID and Instrument cluster. I tried everything before buying replacements - I tried the following:

1. Purchase CD that had all the info in cleaning the ribbon etc. - DID NOT WORK FOR ME!
2. Purchase the ribbons from BMW pixel failure repairs - DID NOT WORK FOR ME! (Too complicated DIY for the type of person I am - well maybe it's really the skill level which is crucial)

I ended up finally ordering from BMW the instrument cluster for US$844 and buying a replacement unit on ebay from seller "germanaudiotech: for about US$300. I'm very satisfied! Now I can sleep! :-)

Hope this helps.