GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 299

If your vehicle has StabiliTrak, this message displays
when the Traction Control System (TCS) is turned off.
Adjust your driving accordingly. See
for more information.
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message displays briefly when a
trailer with electric brakes is first connected to the
vehicle.
This message clears itself after several seconds. This
message also clears if you acknowledge it. After this
message clears, the TRAILER GAIN/OUTPUT display
appears in the DIC.
See TRAILER GAIN/OUTPUT under
and Integrated Trailer Brake Control
System under
information.
This message displays and a chime may sound if the
transmission fluid in the vehicle gets hot. Driving with
the transmission fluid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message clears and
the chime stops when the fluid temperature reaches a
safe level.
or
This message displays and a chime may sound if a turn
for more
signal is left on for 3/4 of a mile (1.2 km). Move the turn
signal/multifunction lever to the off position.
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