you have e53, right?if so: if yo have tv module installed, try disconnecting the navigation module (ONLY after power led stop blinking and remain OFF!!!), you should see tv menu on screen (less graphics...ugly like a 386 bios screen ), so, if all wil work ok (except navigation...) then go for a navigation module (MK4) but, maybe, only after a os refresh...sometimes it helps...the second module i suspect is the radio module, cables (cable looses , improper grounding, etc) and only at last go for a board monitor (from ebay of course...a new one is far too expansive...


regards