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Computer problem
1991 BMW 525 6 cyl Two Wheel Drive Automatic 20300 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.
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.
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.
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.
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.
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