SPONSORED LINKS

1991 BMW 525 computer problems

Tiny
FLYBOY97222
  • MEMBER
  • 1991 BMW 525
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 20,300 MILES
The onboard computer that tells me MPG, Time Date and all the other cool stuff I like to track on my car, has gone dark, I can see the numbers if durring the day but the back light has gone out, but also when I use the dash to pull up the info I only get Time, outside temp, Average MPH, Distance to Empty, and that is all.
SPONSORED LINKS
Tuesday, November 18th, 2008 AT 11:03 PM

8 Replies

Tiny
DOCHAGERTY
  • MECHANIC
  • 9,601 POSTS
The OBC is back lighted with 1.5 watt bulbs that can be replaced. Remove the radio and there is a lever in there to release the OBC. It takes a very small screwdriver and small Allen wrench to remove the radio.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 11:17 AM
Tiny
FLYBOY97222
  • MEMBER
  • 19 POSTS
Thank you very much. But that doesn't answer why I only get partial data on the dash computer now.
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 11:31 AM
Tiny
DOCHAGERTY
  • MECHANIC
  • 9,601 POSTS
To restore full operation of the dash display removing the OBC and replacing the bulbs should reset the functionality of the OBC. It is like control/alt/delete on your computer. If that does not work you may need to disconnect the battery for several minutes to achieve the desired results. Keep in touch.
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 12:21 PM
Tiny
FLYBOY97222
  • MEMBER
  • 19 POSTS
Thank you- I will try both. And keep you informed.
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 12:22 PM
Tiny
DOCHAGERTY
  • MECHANIC
  • 9,601 POSTS
Let me know if you need a radio code.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 1:56 PM
Tiny
FLYBOY97222
  • MEMBER
  • 19 POSTS
Okay- got the OBC out and looks like I need to get the bulbs from BMW? Also I tried unhooking my battery and also just unplugging the OBC but the dash is still giving me partial info. I'm going to try and unhook the battery while I have the computer out.

It never asked for a code? Weird.
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 2:07 PM
Tiny
FLYBOY97222
  • MEMBER
  • 19 POSTS
I had to order the Bulbs online from Pelican- $.75ea and $7.50 to ship.

I also might think it the other problem might be the OBC control unit. Do you know where that is located?
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 3:20 PM
Tiny
DOCHAGERTY
  • MECHANIC
  • 9,601 POSTS
The on board computer is pretty much self contained, there may be something that I just dont remember about the info display, I will try to have a discussion with a contact of mine and see what I can find out ASAP.
Was this
answer
helpful?
Yes
No
Wednesday, November 19th, 2008 AT 3:49 PM

Please login or register to post a reply.

Related Engine Computer Content

Engine Computer
GUIDE
Engine Computer
The automotive engine computer, also known as the ECU, PCM or ECM (Engine control unit, Powertrain control module, Engine control module), is central to a vehicle’s ...
VIEW MORE

Sponsored links