Four problems related to battery have been reported for the 2006 GMC Envoy. The most recently reported issues are listed below.
The tailgate will occasionally not open. The actuator has already been replaced. The electrical system seems to also "act"up when this happens. The remote takes several times to open the doors. We have replaced the battery several times, the dome light does not come on anymore, the stereo turns off immediately when you turn the engine off, instead of staying on until you open one of the doors.
Electrical system has issues. The truck (with a new battery) need to be jumped. Occassionally it will turn without a jump, the radio and other electrical items reset. The stabilitrac light comes on.
Stabilitrac and/or abs system engages when not necessary such as driving on dry, straight pavement at highway speeds. Causes vehicle to decelerate suddenly and almost lose control when brakes activate and motor retards. Electrical system also fluxuates (altimeter bounces from low to hi) causing a loss of power with associated loss of steering, lights, braking controls, at any speed. Problem has been increasing (frequency & severity) from July, 2009 to present (Jan, 2010). Dealer shop did stabilitrac TSB firmware upgrade (and charged me) w/o correcting problem, also retested and "could not find anything wrong":battery is new but problem persists. 55,000 miles, mostly highway/improved roads. This occurs every time, literally, the vehicle is moved: 30-40 miles/day. 1/6/10 engine developed "low growl" noise and rpm dropped from ~800rpm to ~600rpm at parked idle w/o any apparent cause. Now idle at start is normal, but within 1-2 minutes drops and remains low with growl noise.
2006 GMC Envoy xl. Since the car was purchased there have been repeated issues with the service lights. This problem has occurred repeatedly through 2012 where a variety of lights come on. Some stop the car from starting. . . In 2006, service stabilitrack consistently comes on along with 3-56 other lights at the same time. I've been told the connectors are dirty, that I needed a battery replacement which was untrue. Other times the car has gone for service, noone really has the right fix. There is something wrong with all the sensors.