Dim OBC

[Hoody]

Recently i've been having electrical problems with my beast. Mainly not getting a charge to the battery at all. Due to this i've been constantly taking my battery out of the car.

About a couple of weeks ago I went to start the beast up and get a *click* sound then completely nothing. Tried turning the key again and it seemed no electricity was present at all. I immediately went to the trunk and saw my stupid mistake. I had forgotten to tighten the lead on the positive terminal. So while trying to start somehow it had poped off the terminal. I secure it on and go and start the car. Car starts up fine but I noticed something odd with my OBC. The display itself seemed very dim. I tried turning on the headlights and playing with the dimmer but it had no effect.

What confuses me is that the display still shows the information but it is hard as hell to read. Anyone have simliar problems with their OBC? I've tried searching the forums and came up with something related. Maybe just the bulbs need replacing?

[UweM3]

there is a little slider in the OBC with the bulbs soldererd on. They are known to blow. You can get a new one from the dealer. Or convert your old one, buy new bulbs from electric shop, or convert to LED's. I am sure this was covered on here before with a good write up showing the LED conversion.

You have to remove the OBC to get access to the bulbs I am afraid. S***te job

[Dougy Fresh]

uwe is right your there is a little 2w bulb that lights up the obc, it is dead.

You have to remove everything at the center dash, radio, buttons etc.

as for the electrical problems, are you positive the battery is good? If the battery is not getting a charge, test the alternator. Check all the grounds and clean them.

[UweM3]

uwe is right your there is a little 2w bulb that lights up the obc, it is dead.

You have to remove everything at the center dash, radio, buttons etc.

as for the electrical problems, are you positive the battery is good? If the battery is not getting a charge, test the alternator. Check all the grounds and clean them.

forgot to mention, check the charge indicator light in the instrument cluster. That needs to be ok! Replace if not sure if it works.

[Sporty1]

There's astep by step guide to changing the bulbs in the OBC here;

http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00052&Section=02

.......as far as your battery/starting problem goes do as previously mentioned but also check for excessive drains on the system.
HTH

[LeeVuong]

As was mentionned before, it can be the 2W bulb panel. Very expensive for what it is, and a PITA to change. But before you get there, check if all the instrument in the cluster actually work. If you are missing a few, such as RPM and water temp, then check the #7 fuse (if I recal correctly).

[Hoody]

Thanks guys for the help on the OBC light. Bummer that I'll have to take all that out just to get to it. As far as the charging problem. I bought a used alternator from a member here and had it tested at checkers. It tested out fine. I put it in and used a volt meter to see if it was charging the battery. It was putting out a steady 13.8 volts. I've been driving around fine for about a month with the replaced alternator. Something quite horrible happened the other day though. While driving four of my indicators turned on; battery, anti-lock, brake lining, and for some reason my park brake light also stayed on. Durning my charging problems i had noticed when my car would start juicing out and die the first thing that came on would be the anti-lock indicator. i'm guessing thats the first thing that fails under loss of power, but I can't explain for the rest :lostme:.

[Dougy Fresh]

I bet it is the batteries that power the gauge cluster and check panel, they only have a shelf life of 10years. when they start to lose power they can cause funky things to happen like a jumpy tach or indicator lights to randomly come on.
Pull the instrument cluster out and make sure there are no loose or frayed wires too. and inspect the circuit board.

the new batteries can be soldered in.

the batteries used by bmw are Sanyo Laser Lithium CR14250SE (3V) you will need two. They only cost 5$ each so its worth just replacing these before you try replacing the entire circuit board.

here is where I got mine from: http://www.batterystation.com/lithium.htm

good luck

[Dougy Fresh]

the batteries might have changed on the later models so take your cluster out first and have a look at the circuit board before you order any batteries.