I had this happen when I had a defective (worn out) tach amp. Apparanly
it's a bad ground.
Got any aftermarket electronic stuff installed?
What *might* work is pulling fuses one at a time and driving around
for a couple of days that way. Yes some things will be crippled but you
may be able to narrow down which branch of the electrical system is doing
this do you.
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
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