sat nav and dvd questions

[petershamu]

Hi,
car i am picking up next week says disc i/o error so i am either going for a repair or more likely a replace as the screen flickers every now and then as well.

it has a dvd box in the back which i have been told is the sat nav.  now silly question time, does this play dvd's as well??    and do you need to keep the sat nav dvd in at all times?? or do you "load" it.

i googled to replace the unit in the back and i get this
http://www.ebay.co.uk/bhp/bmw-e53-sat-nav

now these look like they have slots in the front, so could i kill two birds with one stone and replace the screen and unit with one of these??

if so which one??  same question does the sat nav dvd have to be in all the time.

sorry for dumb questions.

thanks Peter

[Horizon]

Input output error. Old be as simple as a bad connection on the multi plug on the satnav DVD module in the boot.
Yes, you do have to have the disc in all the time, no they don't play DVD's to the screen.
The aftermarket units don't have DVD based maps, they are stored on a micro SD card in the facia of the unit, they are usually running IGO 8 software which is better than the MK4 BMW nav
To install them you need to run an aditional cable to the radio module in the boot of the X5 if you have a factory nav X5. Some units are better than others, wouldn't like to recommend any in particular.
I would try disconnecting your nav unit and seeing if your flickering screen goes away, then look at replacing your unit or they are repairable . Keeping it OEM
Good luck