Hey Everyone,

I had to take my car to a private certified BMW mechanic don't get me wrong I love to work on cars but I haven't had much time so I could work onit anyways the main reason I was taking it in to the mechanic was a power streering leak that was pretty bad but I went to start the car to drive it over to the shop it didn't want to start luckly I had just signed up for AAA and had it towed to the shop after waiting a while to hear back from the mechanic he calls to tell me that the drain on the battery was due to the Nav system not shutingdown has any one heard of anything like that?

He suggested disabling the Nav system and he wanted to charge me $170 so I am trying to save a few bucks and told him I would take care of that unfortunetly I have not found much on the subject on how to disable the Nav unit I found a PDF on e38.org (great site for ideas and DIY fixes) its showing the NAV unit is controlling praticaly everything from the Radio, GPS, DSC, etc. how can I just disable the part that is causing the drain?

Do you guys think that replacing the unit will solve the issue I was thinking of upgrading to the MKIV unit with the 16:9 screen but I wasn't planning on doing it so soon? if there is a better solution then replacing the unit I would like to know?

Thanks all in advance for your help and attention on this matter,
Steve

Anyone with ideas or suggestions would be greatly apreciated.

Thanks,
Steve

interesting theory. did he say how he determined that the nav was not shutting down? that could be to cause of my aux battery running down. I have two batteries on my 750. I'd just unplug the nav from the back as a test anyway.

Thanks for the input I will find out tomorrow on how he came to that conclusion I was baffaled by it as well.

I wonder if I can try the same thing disconnect the nav but I been looking at some PDF's on the e38.org site and they show the nav computer controlling quite a few things so I was wondering if I disable the nav unit wouldn't that affect the other devices?

Steve

You can check to see if the Nav computer isn't shutting down by leaving your trunk open after shutting off the car. Check to see if the red light is off after the car goes to sleep (approx. 15-20 minutes) after shutting off the engine. You can also check by taking a multimeter reading the voltage at the battery to see if it is draining (parasitic). It is not unheard of for the MK nav units to go bad in these cars. You could disconnect the connectors at the back of the Nav unit in the trunk or try to find the fuse for the Nav computer and pull it. The fuse may be the easier of the options.

***PS****. Remember to wait for the nav unit to completely power down before disconnecting power to it just in case the Nav unit is not the cause of your power drain.

Thanks for the input hypercritic2003 I will definetly try your suggestion as soon as I get the car back I will post my results.

Thanks again,
Steve

Hypercritic, your P.S. poses an interesting question.

If the Indy is right and its draining because the Nav. Comp. won't turn off.
How will the O.P. disconnect the drive properly?
It has to be light off before disconnecting battery or drive.
Hmmmm?
Maybe try and eject the disk and see if it will power off with nothing in the drive to read. Then disconnect.

My .02 cents

If it's not powering off, then perhaps that is because the battery was already disconnected once and the Nav is fried. I never knew of this and I'm sure I've disconnected the battery on more than one occasion before it powered down. I've thought about maybe reloading the hardware
My light does go off. So I don't know if it may still be powered. Having two batteries makes it more difficult to diagnose. But I never have a completely dead battery. So maybe the car going to sleep is what's saving it?
Taking the fuse out might be worth trying. The nav does control a number of things. The most noticable would be the monitor screen will not have a display, but the radio will still play. I have a TV tuner that will run the monitor without a nav.

If you still have the original phone in the car, one other thing to consider is an issue I had with the original Motorola StarTac phone - I always left it in the car and in the cradle, and I went through two batteries before the dealer found a service bulletin that corrected the battery drain from the phone. Just a thought...

Thank you all for your input it is much appreciated cody3 you have a good point I donot use the phone that is in there now (shoot I don't think any of us due) but that is something definetly to look into. RIboater I did infact replace may battery twice at that and I did not take into consideration looking upi how to connect the battery properly I figured should be the same like every other battery I changed out I am thinking I did fry the unit. If that is the case the only thing to do is to replace it correct? can I ran that nav computer for a while? Will it affect anything else?

I will post my results as soon as I get a chance hopefully this thread will help sombody else out.

Hypercritic, your P.S. poses an interesting question.

If the Indy is right and its draining because the Nav. Comp. won't turn off.
How will the O.P. disconnect the drive properly?
It has to be light off before disconnecting battery or drive.
Hmmmm?
Maybe try and eject the disk and see if it will power off with nothing in the drive to read. Then disconnect.

My .02 cents


Alex, I did take that into consideration and it was a bit of a dilemma but I did state after the Nav unit shuts down. If it never shuts down then the unit is most likely fried and would need to be replaced anyways. Just my best guess. :(

In the "leave well enough alone" category... I decided that maybe reinstalling the firmware might reset whatever was wrong. I think my MK3 was also draining my battery. Well I loaded the disc and the programming started. And well past the point it should have finished it didn't. So i tried to eject the disc and it wouldn't. I had to open the drive to manually eject it. Now I can put in a cd and eject it, so there is power, but the light never comes on and I have no Navigation option on my monitor menu. I think I've fried it for good now :(
Lucky for me the TV tuner does a great job of running the monitor. It even lets me use the "select" button on my widescreen which the MK3 would not. Now I can hear those distant stations I could never get using FM A what ever that is? I had FM1 and FM2.
So maybe I don't want to bother with a OEM nav system anymore anyway. Let's face it, even the MK4 is ancient technology compared to the portable units you can buy today.

update:

I let the car sit for a couple of hours and went back to it. Now there was no disc in it all this time. When I turned the key on, I got the screen I was waiting for. "software update complete, hit ok button". So I did. And the MK3 is back to life and driving the monitor instead of the TV tuner. So I loaded my nav disc and that's working also.
NOW let's see if the original reason I started doing this works. Will the MK3 with freshly loaded firmware power down and stop draining the battery. ( I don't have use of the "select" button on the widescreen anymore again)
Also, I'm probably taking out the TV tuner and the DVD player that plays thru it if anyone would be interested?

Hi RIboater,

I know I was supposed to post my result but I really haven't had time to check for the problem I have been disconnecting my battery and reconnecting it every nite I know I shouldn't really do that but It's all I can do at the moment since I need the car to go from work and back also I found out that I have a MK2 unit so I am not sure if the firmware update would apply to my situation unless someone know s something about it. Is there a firmware update for the MK2 Nav unit? if so were and how can I go about it?

thank you everyone so far for you help.

Update:

I forgot to mention on more thing on my last post when I got the car back from the Indy I did as you suggested hypercritic2003 was I let the car sit for atleast an hour to hour and half when I opend the trunk to check the nav units lights they were still on now I don't know if they activated when I opened the truck or if they turnedoff but the dam lights were still on it was late that nite and all I did was discounted the battery I didn't want to take a chance of the battery draining again.

thanks again for the input and suggestions hypercritic2003

Steve

Today was the first very cold morning since I reloaded the firmware. Strange, but my low battery symptom of the monitor not powering up only occurs in the cold. And sad to report it did happen again this morning. So if it IS my nav unit draining the battery, reflashing it didn't fix the problem. So it might be a wasted effort for you to try on your MK2. But if you did want to, just search on E38.org for how.
The highest upgrade the MK2 will recognize is V21. 2-1/81
http://www.bimmerboard.com/forums/posts/29257
If you read through the threads on there, it will teach you how to burn your own disc.
And yes, opening the trunk "wakes up" the nav. At least mine does. Even opening the door does it. I can hear it start running in the trunk.
At least for me, the cold weather is almost gone, and my nav unit and monitor/radio problem will be gone once again. Just another reason to hate winter.

I have that same problem and it had seemed to go away. Now that its getting warmer I unhooked my batterie to reset the car hoping to get rid of my abs, brake, and traction control lights that were caused by cold weather drains it seemed. And now the batterie is getting a hard drain that is draining the batterie to the point the doors wont unlock. Pep Boys said the batterie is weak and so is the alternator. It seems like the weaker the batterie the more problems this great riding car has. Too bad it won't start and hlf the time I have no radio...lol

Hi Steve. I wondered if your mechanic's diagnosis of the Nav not turning off was (maybe) because he's not familiar with the joys of the "constantly running" electronics of our cars. When you opened your trunk that's what causes the car to "wake" from "sleep mode" and thus powered the Nav back on. And if the mechanic was to let the car sit... then open the trunk... the Nav would be powered up when the trunk opened.

I might have missed this above.... but try leaving your trunk ajar (unlatched and pushed down) then waiting the time period to see if the Nav is off. Don't push the button when you open the trunk because that will wake the car again and you'll have to wait.

That MKII Nav unit is VERY sensative and can easily fry itself out with disconnecting the battery before the unit is powered down. I had it happen to me and (if you upgrade to the MKIV player, recommended) you'll be looking at $845 for a remanned player at Bimmernav.com (just an example) or $1,600 for the same unit new from either BMW or Bimmernav. You might think about upgrading (the remanned unit is just fine!) just to do so anyway.

There are a few things in our cars that have constant power (I wish Qsilver7 would chime in with one of his manual pics here) and having a battery tender is highly recommended! If left for a little while the car itself will easily cause the battery to go flat. It might also be advisable to change out the battery (if it isn't fairly new) just from the draining to dead, recharging, draining to dead, recharging... may have damaged the cells in the battery and cause it to not hold a charge.

So before you go and disconnect anything.... try leaving the trunk open to see if the Nav is powering down (as mentioned--when the light stops flashing and you can't hear it recycling the disk). If it is shutting down... try changing the battery out and pick-up a battery tender (pictured below). There are 2 options for the tender. Both require a wall outlet but differ when connecting to the car itself. 1 connects to the battery (or under the hood to the jump connections) via copper clamps and the other that plugs into the cigarette lighter recepticle which will require you having to leave the door or a window/sunroof open to allow the cord to be plugged in. I think the first is a better option (rather than leaving your car open!), have been using it for months now connected to the battery itself (hook up the clamps then plug power into the tender unit) and my battery is always fresh and ready to go.....with NO power loss.

Just something else to think about but I would, regardless, think about picking up the BMW Battery Tender (below) as it will save you from having this problem again in the future. Good Luck with everything! :cool

First option-cigarette lighter plug in.
BMW Part# 82110026663
http://i6.photobucket.com/albums/y248/H2o_TRBO_GTi/82110026663b.jpg


Second Option-copper clamps (Recommended).
BMW Part# 82110406881
http://i6.photobucket.com/albums/y248/H2o_TRBO_GTi/82110406881b.jpg