SI board delete on late model

[packratbimmer]

Calling all electronics whizz kids. >>>> Lets delete the SI boards on our late model cars. I understand that there are many circuits running through the late board, but how complex could it be to make a simple delete board. Tach, econo. and temp. are all that I care about. Who wants to make some money? I wish I knew how...

[TobyB]

uhhhh...

anybody got a paper clip?

t

http://www.wedophones.com/BMWManualsLead.htm

[packratbimmer]

That works on the early cluster for sure. I suspect you might need three paperclips for the late model though - LOL

[Vincenze]

You'll still need a microcontroller to process all signals.
Somebody has to reverse engineer the signals.

There is a thread where a new electronic instrument panel is developed.

[packratbimmer]

Just for fun, I just built up an early cluster (rear loading code plug) and completely eliminated the SI board by using one jumper wire. I am currently running it in my 1989 325i and everything including the cruise is working. I have a 6 button OBC and all looks good there so far - no idea if this would work with 13 button. I put a late model 60L fuel gauge in it and have not filled up yet, but it seems consistent with the level of gas before the experiment. The project exceeded my expectations - the fuel economy gauge even worked and is fluid (not jerky or anything). Would be interesting to see if any of the functions could be jumped on the new style cluster - another bigger experiment for a longer day...

[Gregs///M]

Unlike the early model cluster, the late model SI board on the E30 powers and controls the tach, temp, MPG, SI lights and OBC. SO you would need to build a microcontroller system to deal with all the IO for those gauges and the OBC. Essentially the SI board is pretty much the entire cluster so to "delete" it would be pretty much delete the whole cluster. There is no way to "jumper" the circuit board like on the early cluster. Unfortunately the SI board will have to remain.

On the E28, E23, and E24, the SI board powers and controls all gauges and indicators so the problem is even worse. The cluster harnesses plug directly into the SI board .

[Gregs///M]

The early model SI board is just a controller for the SI lights. Most of the other circuits that are on the late model SI board, are located in the tachometer assembly, on the early model cluster. That is why most of the gauges still work with the early SI board . The early SI board is only half of the SI board, the other half is in the tach assembly.

[packratbimmer]

I would be content to jump the temp gauge (looks simple) and the tachometer (a bit more challenging) - which seems feasible from what I see on the schematics. Not worried about econo gauge, OBC or even cruise for that matter. I like the M3 setup with the oil temp where the econo gauge is located (probably not realistic). I think a class in hypermiling would be much more useful these days in comparison to the econo gauge which must have been novel for the time, but now questionable.

So - anyone up for creating a micocontroller?