Hi All,

I am a newbie to the forum and I was looking for some help on a sat nav problem. I am trying to retrofit a MK4 unit into a 2002 E39 525d Touring, to replace the original MK3 unit.

After reading a lot of the posts on various sites including on here, I stumped up the cash for a MK4 unit to replace my slightly dated looking MK3 CD based unit. I thought it was a case of getting the unit, plugging it in, sticking in the DVD and away I go, but I have not been so lucky

So - here is the problem:

1) MK3 unit working fine - all functions work
2) MK4 unit, plugged in and powers up (LED flashes etc) seems to be reading the disc
3) Blank nav screen (but backlit) and nothing happens, screen does not work or intermittently works when the TV tuner takes over (looks horrible!) - radio etc. still working
4) Tried the update of MK4 with drivers door open, boot open etc. that is available on most sat nav threads - did not do anything and the unit was ejecting the DVD after 1 minute or so
5) I have taken the unit to BMW to be coded to the car, but BMW say that it is not possible to retrofit the DVD unit to my car?
6) MK3 unit back in :-( - working fine.

So I guess my question is - is there any reason why the unit I have would not work with my system. The DVD unit I have is actually out of a 2002 525 Touring (told by BMW - not that I think it matters!) so I cannot see any reason why it would not work.

The Technician at BMW said that the unit was manufactured 6 months later than my car, therefore it would not work.

I have a suspicion that because they did not supply the unit, they dont want to fit it (understandably) but on the plus side of wasting 2 hours of my day, I got a free valet! :-)

I hope this post is not too long and waffly, missing any information or broken any forum rules (I am a newbie!)and anny help sat nav gurus could provide would be great.

Thanks in advance

Chris