Side alert notification

when you are reversing on a ford explorer limited it beeps at you when a car in coming from the side. there should be an arrow on you my ford touch screen showing you which side the car is coming from. when i revers i watch the screen only so i hear the beep not never sure which side to turn and look. 
Curran F 12/11/2013
If you have Blind Spot Notification it blinks the LED in the mirror of whichever side a vehicle is approaching while you are in reverse.