GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 291

On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message may display and a chime
may sound when one of the following conditions exists:
A trailer with electric brakes becomes
disconnected from the vehicle.
If the disconnect occurs while the vehicle is
stopped, this message clears itself after a
short time.
If the disconnect occurs while the vehicle is
moving, this message stays on until the ignition
is turned off.
There is a short in the wiring to the electric trailer
brakes.
When this message displays, power is no longer
available to the trailer brakes.
As soon as it is safe to do so, carefully pull your vehicle
over to the side of the road and turn the ignition off.
Check the wiring connection to the trailer and turn
the ignition back on. This message clears if the
trailer is reconnected. This message also clears if you
acknowledge it. If this message still displays, either your
vehicle or the trailer needs service. See your dealer.
See Integrated Trailer Brake Control System under
for more information.
This message displays and a chime may sound if the
driver door is not fully closed and the vehicle is shifted
out of P (Park). Stop and turn off the vehicle, check the
door for obstructions, and close the door again. Check
to see if the message still appears on the DIC.
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
See
. To avoid added strain on a hot engine, the
air conditioning compressor automatically turns off.
When the coolant temperature returns to normal, the air
conditioning compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer as soon as possible to avoid
damage to the engine.
This message displays when the engine oil becomes
hotter than the normal operating temperature. Stop and
allow the vehicle to idle until it cools down. See
.
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