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Augusto89
03-07-2012, 03:31 PM
Hi, sorry for my English , my name is Augusto, I'm from Argentina and i having problem with the obc (18 bottoms) of my 1992 325is. From one day to another the obc not start, I check 12v of pin 8 and ground of pin13 from white connector and it is working. I've seen it turn on a couple of times when I try start the car in a very rare situation where the obc start but the car does not, but only for a few seconds, then I try again and car star but the obc does not. I having this problem 6 months ago. Any idea? Thanks.
MParallel
03-07-2012, 04:49 PM
Make sure the 4 small bulbs that light the dot matrix display aren't broken.

Pop the OBC out and check the bulbs. They are right on top of the unit.
JDStrickland
03-07-2012, 05:11 PM
Sorry, your English a little bit of a problem.

The OBC does not start, it is only able to start. You have to press a button to make it start.

As has been said, you can remove the display unit and see four lamps along the top. The lamps are required to back-light the display -- no lamps, no display. This does not explain why you get something sometimes, but not all of the time.

The Dot-Matrix has been known to fail. But again, this does not explain why you get something once, but not the next time.
Augusto89
03-07-2012, 07:29 PM
The Lamps look all fine.
It can be a sensor that causes a malfunction or something related with battery?
JerCotter7
03-07-2012, 08:20 PM
You checked the ground and 12v and both are fine? What about the remote? Do the buttons light up with the rest of the lights in the car?

Check pin 14 and 9 of the black connector for 12v I think.

They should be powered when the radio is on.
MParallel
03-07-2012, 08:38 PM
The Lamps look all fine.
It can be a sensor that causes a malfunction or something related with battery?

Yeah "look". It wouldn't be the first time I thought a bulb was fine, except it wasn't.
MParallel
03-07-2012, 08:41 PM
The Lamps look all fine.
It can be a sensor that causes a malfunction or something related with battery?

Yeah "look". It wouldn't be the first time I thought a bulb was fine, except it wasn't.
JDStrickland
03-07-2012, 08:42 PM
The Lamps look all fine.
It can be a sensor that causes a malfunction or something related with battery?
The LOOK fine? Do they turn on?
JerCotter7
03-07-2012, 08:52 PM
Yeah "look". It wouldn't be the first time I thought a bulb was fine, except it wasn't.

You would still see the information on the screen if the bulbs were gone? Just during the day only?

I've only the far left bulb gone but I can still see the information there. Just a lot darker than the right side.
JDStrickland
03-07-2012, 08:56 PM
You would still see the information on the screen if the bulbs were gone? Just during the day only?

I've only the far left bulb gone but I can still see the information there. Just a lot darker than the right side.
There are 4 bulbs. If one is out, then there are 3. The section of the display in front of the dead bulb is dark, but it is still lit be the adjacent bulb(s). If all of the bulbs are out, then the display will be all but impossible to see.
JerCotter7
03-07-2012, 09:12 PM
There are 4 bulbs. If one is out, then there are 3. The section of the display in front of the dead bulb is dark, but it is still lit be the adjacent bulb(s). If all of the bulbs are out, then the display will be all but impossible to see.

Never knew it needed them to function at all. Thought it was just during the dark. Thanks.
JDStrickland
03-07-2012, 09:15 PM
Never knew it needed them to function at all. Thought it was just during the dark. Thanks.
The display is dark unless the bulbs are on. It is a backlit display. No back light, no display.
MParallel
03-07-2012, 09:47 PM
With the bulbs off you can see the display if you like put it right in front of your eyes, at correct angle so some ambient light falls on it, but other then that, what JD said.
Augusto89
03-07-2012, 10:20 PM
You checked the ground and 12v and both are fine? What about the remote? Do the buttons light up with the rest of the lights in the car?

Check pin 14 and 9 of the black connector for 12v I think.

They should be powered when the radio is on.

Yes, the buttons light up with the rest of the lights in car.

Tomorrow I'll try putting the bulbs in the instrument panel but I'm sure they are fine.

I checked all the bulbs and they work fine.