<E34> Water Spots on Glass & OBC Not Working

["Nelson, Mark J" <Mark.Nelson@xxxxxxxxxxxxxx>]

I have a 1989 535i with original glass.

1.  Does anyone know how to remove hard-water spots on the side and back
windows?  I tried Bon-Ami, but it didn't seem to help.  I'm guessing that
the soft glass on BMW's is easily etched and after 10 years I've got spots.

2.  The MPG and AVE MPH functions are not working on my OBC.  The MPG always
reads 6.0 and the AVE MPH reads 0.1.  However, the speedometer and fuel
gauges seem to work fine, which I think means that the speed sensor and fuel
level sender are good.  Anybody have some suggestions where I should look to
diagnose this problem? 

Thank you,
Mark Nelson
Seattle, WA
BMWCCA 161283
1989 535i

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