Actually bro,when I first got the car,as soon as you go into reverse,the PDC diagram comes on on the Idrive but it won't beep untill it's close to an object just like how the front is now.It only beeps when I'm approaching something but while the front is ok,the back starts beeping the minute I go into reverse and it stays beeping even after getting to drive mode and driving off.Then it goes off after a certain speed as how it should.