BMW Repair: 1998 750il Navigation System, nav system, 750il

Question
Local dealer can't work on the computer for the Nav System; wants about $2500 from replacement.
Does anyone repair this computer?

Answer
If it came from the factory with the system it may cost that much and being it is a 750 I would assume that would be the price.But before replacing the computer I would be checking the wiring,grounds and how they are routed.If is out, it may have a manufacturers name on it go from there.