See also:

Customer Assistance Offices (U.S. and Canada)
GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

Setting the Clock
To set the time and date for the radio with CD, DVD, and USB Port: 1. Turn the ignition key to ACC/ACCESSORY or ON/RUN, then press to turn the radio on. 2. Press to display HR, MIN, MM, DD, YYYY ( ...

Battery Load Management
The vehicle has Electric Power Management (EPM) that estimates the battery's temperature and state of charge. It then adjusts the voltage for best performance and extended life of the battery. When t ...