ive just fitted a ford 6006e headunit to the wifes zetec focus, it has auto volume control so it increases the volume depending how fast you are driving,everything just plugs in so its idiot proof but the auto vol doesnt work,at first it didnt show on the menu screen [as though it couldnt detect it fitted to the car] however after i had a drive it appeared on the menu,i switched it on and adjusted it to max but still no good, how is this wired up or what sensor on the car actually controls this function?

 

it picks up from the road speed sensor

 

does this control the speedo as well then?

 

did you get it from a fiesta 2006 onwards? As the speed input was removed from that date on and the dash tells the radio what speed the car is doing via the CAN BUS system.

 

it was from an rs focus so would be 02/3, im going to try it in mine tomorrow just to rule out any fault with the head unit,whats a can bus when its at home?

 

You could always just turn it up by hand!

 

Its a data stream between all the electronic units in the car.