Calling on the OBC gurus

[Cobra]

89 535ia

My OBC's illumination went out and could only be seen at night (barely) when the headlight switch was on. The stalk/instrument display functioned normally.

I changed the bulbs in the OBC, illumination lasted for a second and now the OBC does not lightt at all day or night. The stalk/instrument display seems to functions normally.

I've checked the connection at the back and it's solid. My questions are:

1) Does my OBC sound like it's toast? Is this rather common?
2) Are all E34 OBCs interchangeable?
3) How much should I be paying for a good used one?

Thanks in advance and take care,
Dan

[Tiger]

3 bulbs? You changed all three bulbs? Did you solder new bulbs into the contacts? Or did you buy the bulbs from BMW?

[silver-e34]

dan if you didnt get the bulbs from bmw then the bulbs might be loose or not installed properly. if your obc is toast then you are in luck a used one will run you 15.00 + s/h look in here http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=50459&item=2470241756

[Cobra]

Thanks for the quick responses.



3 bulbs? You changed all three bulbs? Did you solder new bulbs into the contacts? Or did you buy the bulbs from BMW?

No. Do all three have to be good for it to illuminate? No solder. There's no room in there. No, I got them from Bruno off an old cluster.


Silver thanks for the link, that's cheap (too bad I'm in Canada). I've checked the bulbs before installing and they worked. I did notice that when testing the negative side of the OBC strip there was no ground (my tester did not light) and I'm not sure where to go from here. I figured swapping in a good one would tell me where the problem is or isn't.

Thanks and take care,
Dan

[shoptb]

Cobra,

I had the same exact problem myself when changing out my OBC bulbs. It worked great for a couple of days, then the bulbs just went out one by one. Now, the OBC is not illuminated day/night at all. It is still working just fine, as the data is transferred to the check control display just fine. I got my bulbs from BMW, and they worked fine before. Not sure what the deal is.

Was wondering if my LCD went bad??

[Warren N.CA]

bulbs so they mate properly with the PCB traces that serve as stationary terminals.


89 535ia

My OBC's illumination went out and could only be seen at night (barely) when the headlight switch was on. The stalk/instrument display functioned normally.

I changed the bulbs in the OBC, illumination lasted for a second and now the OBC does not lightt at all day or night. The stalk/instrument display seems to functions normally.

I've checked the connection at the back and it's solid. My questions are:

1) Does my OBC sound like it's toast? Is this rather common?
2) Are all E34 OBCs interchangeable?
3) How much should I be paying for a good used one?

Thanks in advance and take care,
Dan

[Cobra]

Yeah, mine was working just fine (sending the info to the CCD) until I unplugged the OBC to re-seat it. Now I don't see the proper time date, etc. instead I get dashes. If you figure this one out please let me know how, I will do the same.

Take care,
Dan

[Cobra]

Thanks Warren, the tabs already look bent but I'll try bending them further.

Is this set up like the old Xmas lights where if one bulb goes, the whole thing goes?

Take care,
Dan

[Warren N.CA]

light up. But sometimes the bulbs come with their terminals bent incorrectly. You must be sure that both contacts are mating correctly with the traces on the board, or they will not work reliably.



Thanks Warren, the tabs already look bent but I'll try bending them further.

Is this set up like the old Xmas lights where if one bulb goes, the whole thing goes?

Take care,
Dan