BMW E38/E39, TV without NAV - should it 'just work'.

[Chalkie 1]

My E38 Mk 4 Nav and widescreen video module work great. 16:9 display. However, when I remove the Nav (doing some troubleshooting) then I only get a black screen on the monitor. Hmmm...I thought that should just work. Any wiring changes required?

[jonoe30 53]

Having helped a friend with the system on his car, as far as I'm aware the nav system is actually the brains of the monitor (it drives the menus for the system) and everything else connects through that module (e.g. TV & Radio modules). There will be more knowledgeable people on here who will know for sure.

[Chalkie 1]

I've answered my own question: yes, it should just work. And now it does. Although I had removed Nav, then left car off overnight, I still had black/blank image on my monitor. I then dropped my kids off at school, so car was off and doors closed for hmmm maybe 10 mins. When I got back in, it was working. Am pretty sure this is same behaviour I saw previously. Couple of possible logical answers in there as to how it registers/deregisters units I guess.

[Chalkie 1]

Having helped a friend with the system on his car, as far as I'm aware the nav system is actually the brains of the monitor (it drives the menus for the system) and everything else connects through that module (e.g. TV & Radio modules). There will be more knowledgeable people on here who will know for sure.

You're correct, if the Nav is present: it will drive the monitor and the menus. However, if it's not present, then system will 'fall back' to having the video/TV module to drive the monitor & you'll see the older style menus displayed. You'll also get day/night mode if you are just using video/TV module. I wish Nav had that feature.

[hotwire 352]

^^^^ Yes correct Nathan. A car with TV but no nav - the video module controls the screen graphics. When a nav unit is present - it overides the video module & it creates the graphics Once the nav unit is disconnected, the car needs to go to sleep & reboot for the video module to supply grahics