[M_coupe]

hi everyone. this morning my car wouldn't start, next my nav screen went blank...need a new battery. after replacing the battery everything else works but my screen will not come back on! is there a reset button or something?? any help will be much appreciated.

 

[chrisj]

Do the controls on the Nav unit function (radio power, tuning, etc) ?
Do you see any change in the screen when you open the car door? The screen has a backlight which may be on even if nothing shows on the screen - it's a separate piece from the LCD itself.

The Nav screens are very sensitive to power interruptions, though I haven't heard of a failure from the battery dying. The problems usually occur when the battery is disconnected before the Nav system has shut down.

Was the battery completely dead when you disconnected it? If not, did you wait for the Nav unit to shut down before disconnecting the battery (rule of thumb is to wait 5 minutes - red light on the Nav computer turns off)?
When you connected the new one, did you connect it and tighten it down only once (didn't disconnect after the car first got juice)?

Sorry for all the questions :blabla: I have some experience with Nav screen failures and the components involved, so trying to dig a little for more info.

 

[M_coupe]

Chris,
thanks for replying.

Yes, all the controls work fine. I can see the screen change in shade but nothing displayed.
When i first tried to start, all i heard was clicking. Next i turned on the radio to check if it worked...which it did. After a minute, my screen goes blank.
I replaced the battery and car starts right up, radio plays no problem but no display. Yes, i tightened down the battery once. I did a search but no available solution.:sad1:

Do the controls on the Nav unit function (radio power, tuning, etc) ?
Do you see any change in the screen when you open the car door? The screen has a backlight which may be on even if nothing shows on the screen - it's a separate piece from the LCD itself.

The Nav screens are very sensitive to power interruptions, though I haven't heard of a failure from the battery dying. The problems usually occur when the battery is disconnected before the Nav system has shut down.

Was the battery completely dead when you disconnected it? If not, did you wait for the Nav unit to shut down before disconnecting the battery (rule of thumb is to wait 5 minutes - red light on the Nav computer turns off)?
When you connected the new one, did you connect it and tighten it down only once (didn't disconnect after the car first got juice)?

Sorry for all the questions :blabla: I have some experience with Nav screen failures and the components involved, so trying to dig a little for more info.

 

[dmz]

There is a good chance that you might have fried the flash memory of the NAV unit. When you shutdown your car, NAV have to stay on for up to 5 mins to shutdown the system properly. If your dead battery cut power before the shutdown process is done you might have corrupted the firmware. The only thin you can do now is try to reinstall the NAV software from a CD.

 

[bmwusa]

I concur with the others there is a chance you may have fried your nav, I froze my nav up once trying to install the software and I went to the dealership and skirted the issue that I was messing around with the software, and just told them that I disconected the battery, and they then proceeded to show me a service bulletin that shows that if the Nav is not shut off prior to power removal there is a strong likely hood of the memory being correpted, thus rendering the device useless, best of luck I hope you can get it working, Josh

 

[chrisj]

Chris,
thanks for replying.

Yes, all the controls work fine. I can see the screen change in shade but nothing displayed.
When i first tried to start, all i heard was clicking. Next i turned on the radio to check if it worked...which it did. After a minute, my screen goes blank.
I replaced the battery and car starts right up, radio plays no problem but no display. Yes, i tightened down the battery once. I did a search but no available solution.:sad1:

Ooh - the clicking is bad. When you get that point, power to the car's electronics is interrupted as all the juice is going to the starter. That could mimic rapid battery connect/disconnect, which is very bad for the Nav.

When you say "After a minute, my screen goes blank" - are you saying this happened once after you hooked up the new battery (you had the display for a minute, and then it went away and never came back)? If this is the case, things are most likely bad.

The backlight is turning on, which is causing the change in screen contrast. I have a failed Nav unit that has the opposite problem - the LCD works, but no backlight.

I would try dmz's suggestion, if you have the Nav firmware CD. I have a feeling it's probably in the display, but it can't hurt to try reflashing the Nav firmware, especially since you had the clicking when trying to start.

cheers,

Chris

 

[M_coupe]

so a battery dying before i shut down the onboard monitor could have caused this.... I didn't change the or disconnect the battery until after the screen had died. Thanks for the help guys...I guess i need to make a trip to the dealer.

 

[ard]

If it is under warranty, you may want to just leave out any explanation other than "nav is not working"...

A

 

[Lust4Life]

There is a 1 amp, in line, blade fuse located in with the electronics/changers etc. in the boot that you need to check.

It is black, in a black holder, and in the dark so you need a torch but this can pop and you'll just get the backlight on the screen and no display.

Cheers,

Phil

 

[drewdwn]

NAV BLANK SCREEN FIX

Not sure if this was fixed but check out this thread


http://www.m5board.com/vbulletin/showthread.php?p=711586#post711586