I just got the car back from the dealer for a convertible top hydraulic hose replacement and, while driving home, I noticed that the Nav screen was black with nothing on it. I figured that they must have turned it off while services so I hit the on/off switch and nothing, not even the clock. I checked the Nav disc in the trunk and ejected it and reloaded it but I cannot get anything on the Nav screen. I immediately called the dealer and the service advisor suggested that something needed to be reset since they disconnected the battery during the hydraulic hose replacement and he is supposed to call me back.

In the meantime, do any of the gurus out there have any suggestions for me to try in the meantime?

Thanks,

Doug

 

I wonder if they accidently disconnected the NAV unit...it is close back there to all of the hydraulics.

 

That was my guess so I took a quick glance in the area around the hydraulics and the Nav unit but did not notice any disconnected wires. Maybe I should look more closely. I looked closely at the screen with the key turned on and I could swear that I saw something flicker faintly but it could be my imagination. I guess I'll just have to drop by the dealer and have them take a look.

This is a bad omen as the one thing I hated most when I owned a BMW was that the dealer I used (where I bought the car) either (1) could not fix a problem the first time or (2) fixed the problem but broke something else. This was an absolutely chronic problem for the 6 years I owned that car and is largely responsible for my shying away from another BMW.

I realize the hose replacement is quite an adventure so I am not that upset that maybe something was inadvertently disconnected but they should have tried everything out before returning the car. For that matter, I had better try out the top to make sure that goes up and down okay.

Doug

 

Brought the car in today and they found a wire that was either disconnected or broken and the nav is now fixed. However, there is now something else weird with the trip computer. All of the data for trip A and trip B ended up getting reset. I expect this should be the case since the battery was presumably disconnected for the nav repair. However, the battery was also presumably disconnected for the hydraulic line repair and the trip computer was not reset during that repair. But the weird thing is that I reset both trip A and trip B to zero and the instantaneous fuel use reading looks correct but the average fuel use looks incorrect (much too low based on the instantaneous). After disconnecting the battery, does it take a while for the trip computer to recalibrate or reset itself to behave correctly?

Doug

 

That is normal. Even when you manually reset the trip computer, it takes some averaging to bring it all back into perspective. I would not pay much attention to it until you have 10+ miles on the reset.