E-30 instrument cluster and OBC questions

[JHahn22@xxxxxxx]

Hello everyone,
The other night the lighting behind my speedometer and fuel guage went out.  
Now I can't see how fast I am going at night.  I know I've heard of other 
problems with things going bad in the instrument cluster on these cars (mine 
is an 89 325i) and I'm wondering if there is anything else that I should 
replace while I'm in there.  Service indicator battery thingy or something 
like that seems like it keeps getting mentioned from time to time on here. . .
I haven't checked Bentley yet, but I think I saw the process described in 
there before.  Are there any GOTCHA's that aren't covered in the Bentley book?

The second question is just a curious one.  What is my OBC trying to tell me 
when I push the 1 and 1000 buttons at the same time?  It popped up some 
display that said something like 30L (+ or -).  Also, there was some other 
combination of number keys that I pushed and it showed some other weird 
display. . . 4.6 . . .and some other stuff that I can't recall.   Are these 
some sort of fault codes?  Or is my car possessed?

Lastly, I was out at the Texas World Speedway in College station this 
weekend, watching the Porche club play.  Saw some very nice BMW's as well, 
anyone else on here make it out there?
Thanks for any tips,
Jake Hahn
89 325i
87 Alfa spider
Bryan, TX

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