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SI Board Swap
E30 M3 Valve Adjust
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E30 SI Board Replacement
Also: removing instrument cluster

When I first purchased my 1988 M3 the SI lights along the lower portion of the dash were all fully illuminated.  I purchased a reset tool and followed the procedure but it would not take.  I learned this is the classic symptom of worn out SI Board batteries.  These batteries are intended to save the service indicator memory in case you disconnect the car's main battery.  When the car is running it recharges the SI board batteries.  But over time they lose their ability to hold a charge and that is when the SI system starts to go haywire.  The LED's will come on and cannot be reset.  Eventually your gauges can start to act funny (tach, temp etc.)  At his point it is time to replace the batteries.  BMW did not make this particularly easy, the whole instrument cluster has to be pulled out to get at the batteries.  Some people solder in a remote connection so that the batteries can be stored farther down above the pedals.  This makes them much easier to access the next time they need replacing.  However, the modern class of batteries is far superior to what our cars originally came with.  The new (NiCad) batteries should last for quite some time.  Below you will find an outline of the procedure that I followed to replace the SI Board (and the offending batteries).


Select the step of interest at right »

Once you are at one of the steps you can skip sequentially forwards (or backwards) through the other steps. Or you can come back to this menu to select another step.

Each step contains a description and a photo of the procedure in question.

  1.   Removing the lower trim panel
  2.   Removing the instrument cluster trim panel
  3.   Removing the Instrument Cluster
  4.   Unhooking the Electrical Connectors
  5.   Color Coding of the Connectors
  6.   Opening the Instrument Cluster
  7.   Features of the Instrument Cluster
  8.   Pulling the SI Board from the Cluster
  9.   How the SI Board is Situated
10.   Details of the SI Board


Home
Back to Maintenance
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SI Board Swap
E30 M3 Valve Adjust
E30 M3 Fuse Box Diagram