Turn Signals When Towing a Trailer
The turn signal indicators on the instrument panel flash whenever signaling a turn or lane change. Properly hooked up, the trailer lamps also flash, telling other drivers the vehicle is turning, changing lanes or stopping.
When towing a trailer, the arrows on the instrument panel flash for turns even if the bulbs on the trailer are burned out. Check occasionally to be sure the trailer bulbs are still working.
See also:
Taillamps (Chassis Cab Models)
A. Backup Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
To replace one of these bulbs:
1. Remove the four screws.
2. Lift the lens off the lamp assembly.
3. Turn the old bulb counterclockwise and ...
Turning the RVC System On or Off
To turn off the RVC system, press and hold ,
located on the inside rearview mirror, until the left indicator light turns off. The RVC display is now disabled.
To turn the RVC system on, press and h ...
Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors.
Call 1-800-GMC-8782 (1-800-462-8782), or write:
GMC Customer Assistance Center
P.O. Box ...





