head lights, nav screen, fan motor

[coldwell]

2002 bmw 530i
Lately my battery has been going dead.so I would charge it and it would be great for a couple weaks.now it goes dead almost every night.And with the hood up I can hear a fan motor on low and then go off after a min.
before I had time to diag it my battery went dead again and this time my nav screen did'nt come on and my head lights in auto mode only come on at night.
When I checked my mk3 nav system . the power light is not on, but it will let me eject the disc.
my radio works and so does my cd player.:help

[Corey G]

Search FSU or Final Stage Unit

[TwinTees]

I change my battery once on my '99 528iT. It went dead again. Turned out the nav computer was toasted and would run all the time. I replaced it with an ebayer. It went bad too after a month or two. Turns out, the antenna on the roof (central locking or some such antenna) had a crack in the rubber grommet on the base where it seals the roof. Sure enough, water would leak and run right down on the nav computer!. I see your car is an sport wagon too. Might want to check that grommet. You have to buy the whole antenna, but you only need to use the grommet - a $100 grommet!

Live 'n learn...

[coldwell]

It looks like my head lights and fan are working.Still no nav screen.
Oh my car is a 530i, not a sport wagon.

[miketheyid]

It looks like my head lights and fan are working.Still no nav screen.
Oh my car is a 530i, not a sport wagon.

Hi there had same problem with my 530i and took a while but found the cause and all running well for over a month now! AC/HEATER module has 12 prongs very easy done mine in about 10 minutes. Part goes behind centre console on floor part. Undo 2 screws holding small part of carpet and should see another 2 screw fitted to this module???? Undo these unclip the wires plug new one in and heavenly no flat battery anymore!!!!! Goodluck let me know if its worked for you. They are a problem over here on most bmws but have upgraded them now.... Just noticed that mine is same year as yours too, same model same year got to be the same problem & remedy:-)

[coldwell]

no more battery running down.I installed a new battery.
Need my nav screen back.How do I know what part is bad???
I need a good wiring diagram.
If the nav unit in the trunk is unpluged would it still say BMW when the door is open???
How do I know if I have a bad screen or nav unit???

[miketheyid]

no more battery running down.I installed a new battery.
Need my nav screen back.How do I know what part is bad???
I need a good wiring diagram.
If the nav unit in the trunk is unpluged would it still say BMW when the door is open???
How do I know if I have a bad screen or nav unit???
If the tv screen does not have sat nav option on menu screen its the nav unit in the boot. My power light stayed on all the time and would eject the disc but not on the menu display!!! New unit and all working. Also i fitted a new battery but that went dead about a week later, hope yours is ok if not it will be that ac module.