I'm convinced there must be a jack that I am not able to locate. This is not my vehicle but I'm attempting to help a friend who believes his only option is to purchase a new radio with the jack installed. The aux jack in my VW was hidden in the glove box and even then, I looked over it thinking it was a counter sunk screw hole. Does anyone have direct knowledge regarding the Sierra, if an aux jack exists or not?
I appreciate any feedback.