Chevrolet Optra 2004 Owner's Manual page 135

Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven in kilometers.
Trip Odometer
The trip odometer can record the number of kilometers
traveled for up to two trips.
You can cycle between the odometer and trip odometers
A and B by pressing the reset button located in the
lower right area of the speedometer. By pressing the
reset button, you can tell how many kilometers have
been recorded on either Trip A or Trip B since you last
set the odometer back to zero.
To reset each trip odometer to zero, press and hold the
reset button. The reset button resets only the trip
odometer that is displayed. Each trip odometer must be
reset individually.
Tachometer
Notice: If you operate the engine with the
tachometer in the shaded warning area, your vehicle
could be damaged, and the damages would not
be covered by your warranty. Do not operate
the engine with the tachometer in the shaded
warning area.
The tachometer displays
your engine speed in
revolutions per minute
(rpm).
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