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RE: oil pressure icon blinking on '91 200Q

I decided to eliminate some possibilities.  I checked the resistance on the
oil pressure sending unit at both the 'KW' and 'G' posts.  Following
Bentley's recommendations, I let the car warm up until some time after the
fan came on, and then shut it off.  The resistance at 'G' terminal under
shut-off, idle and 3000 rpm conditions all conform to specs.  At the 'KW'
terminal, resistance is infinity at idle, and .3 ohms at shut-off, as per
specs.  (I'm always impressed when an electrical appliance in an area of
sustantial heat specs out after years of use.)  The terminals, however, had
some 'green' buildup, which I cleaned off with a tiny flat file.  Then I
sprayed the male and female connectors with 'DeoxIt D5', which I highly
recommend for cleaning up electrical contacts.  So if this doesn't solve the
problem, then it's either the 1.8bar pressure switch or a problem in the
circuit board.  My guess is that it's not the switch, and with any luck,
this takes care of the problem.  I pass this along, since a number of
listers have had the same problem.  Maybe there's a virus in '91200Qs with a
lag time of 7 yrs.

- Jim