Buick 1993 Roadmaster Owner's Manual page 121

Volts Gage
This gage shows voltage in
the electrical system. The
normal range is 11 to 15
volts. If the gage reading
staysin either red range,
have your Buick dealer
check the electrical system.
Tachometer
I
The tachometer tells you.how fast the engine is going. It
displays engine speed in revolutions per minute (RPM).
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