Report "My 1999 Chevy Blazer has 4-wheel drive problems. The problem begins when I start the blazer. Sometimes when it starts, the indicator lights on the shift buttons work fine and 4-wheel drive will shift without a problem. Lately, when I start the blazer one of two things will happen. 1.) the buttons for the 4-wheel drive do not light up or function at all. When this happens the "service 4-wheel drive" light appears. or 2.) the buttons light fine and the 4-wheel drive seems to work. Since it works sometimes and other times it does not, any suggestions? Also, when I restart the vehicle it sometimes will fix the problem. Thanks!"