e28 U.S.-spec instrument cluster question / S.I. LEDs

[Tim in N FL]

Hi Gang,

The instrument cluster in my "new" 87 535i recently started lighting up
the two far right hand side LEDs when the car is OFF (one yellow, one red LED).
This instrument cluster's S.I. board was just recently repaired/updated and has been
working fine. However, I have not been driving the car very much in the past month.
When I crank the car, the two LEDs go out but "Service Inspection" light comes on and remains lit during normal operations. No other symptoms noted. Any ideas what might be causing these symptoms?

Thanks guys,
Tim :@

[shifty]

Do the batteries make it do that, too? Most people just remove the batteries from the SI board so you never have to worry about the SI lights again.

[RonW]

Originally posted by Tim in N FL
The instrument cluster in my "new" 87 535i recently started lighting up the two far right hand side LEDs when the car is OFF (one yellow, one red LED). This instrument cluster's S.I. board was just recently repaired/updated and has been working fine...When I crank the car, the two LEDs go out but "Service Inspection" light comes on and remains lit during normal operations. No other symptoms noted. Any ideas what might be causing these symptoms?

Yeah, but you won't like it. My theory is that the board was improperly rebuilt. The most likely culprit, assuming the batteries were replaced, is a bad solder joint. These boards are notorious in that department. I've fixed numerous boards by reflowing EVERY solder joint. A very time consuming and methodical job. But it worked. I also had a board that fractured several of its traces for some reason. I fixed that one by jumpering the bad traces. There were about six of them.

I have to ask: Did you try resetting the SI lights?

[Edited 8/24/2008 to enable BBCode]

[Layton]

Tim,

Try what RonW suggested first: Reset your service indicator lights.

There is a very simple method to do this -- I've been using it for years. Read through the BMW Service Indicator Lights FAQ for information and how to build yourself a very high-tech reset tool!

[Tim in N FL]

RonW and Layton,
Thank you very much for your thoughts on this "issue". My Dad is an electronics technician (now retired) and had built up the high-tech reset tool for me back when
I owned my white 535is. It works great! Hopefully, the reset will do the trick...doubtful though as RonW's reply had an ominous tone to it. The PO of the car spent about $300 rebuilding the cluster but....not sure who did the work. We'll see what happens. If all else fails...will put my soldering skillz to work and if that doesn't work...will try Shifty's idea
Cheers,
Tim