GMC 2006 Sierra - Manual (Page 211)

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 either miles (used in the United States) or kilometers
(used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
hour meter, turn the ignition off, press and hold the
reset button for at least four seconds. The hour meter
will be displayed for up to 30 seconds, or until the
ignition is turned on. See DIC Operation and Displays
on page 3-53 for more information.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button, located on the instrument panel
cluster next to the trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
See DIC Operation and Displays on page 3-53 for more
information.
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