Vehicle Messages
Messages displayed on the DIC indicate the status of the vehicle or some action may be needed to correct a condition. Multiple messages may appear one after another.
The messages that do not require immediate action can be acknowledged and cleared by pressing 
(Set/Reset) or the trip odometer reset stem.
The messages that require immediate action cannot be cleared until that action is performed.
All messages should be taken seriously and clearing the message does not correct the problem.
The following are the possible messages and some information about them.
If the vehicle has a diesel engine, see the Duramax® diesel supplement for more information.
See also:
Online Owner Center
Manage your vehicle (U.S.) at gmc.com. Click on “Owners,” then “Manage My GMC/Owners Login.”
Information and services customized for your specific vehicle — all in one convenient place.
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Cellular Phone Usage
Cellular phone usage may cause interference with the vehicle's radio.
This interference may occur when making or receiving phone calls, charging the phone's battery, or simply having the phone on.
T ...
Lumbar Adjustment
Power Lumbar
Eight-Way Power Seat Shown, Four-Way Similar
A. Lumbar Switch
If available, press and hold the front or rear of the switch (A) to increase
or decrease lumbar support. Release the s ...