I have a 2006 jeep commander with the 5.7 v8, 4 wheel drive. When i am driving it, the lights flash from high?

I have a 2006 jeep commander with the 5.7 v8, 4 wheel drive. When i am driving it, the lights flash from low beam to high beam. Then the lights will flash on and off. The air conditioner shuts off and all the interior lights go out and the speedometer quits, as does the tachometer. Also sometimes when i am going down the road, i hear a loud noise from the rear like the breaks are locking up. Any suggestions where to start???