Speedo & Tach not working

[TexasTerp]

So I picked up the following euro cluster a few weeks ago:

http://www.r3vlimited.com/board/showthread.php?t=255670

(disclaimer: wnamane is a great seller, we did a fair trade I have absolutely no problems with him at all.)

The fuel and temp gauges work but I'm not getting any response from the speedo and tach.

The cluster is from an m40/2 powered car. I've swapped in a good working 325i coding plug. I'm running a 2.7i engine with late model harness and 173 e30. The car is an 86 325es.

Other than the SI board possibly being bad, is it at all possible that something else is wrong?

I have a slightly odd combination of parts which is the only reason I have to ask.

[Rsully70sev]

Damn, that's a tough one man. I can imagine your frustration/dispointment (not directed at wnamane) but simply because that beautiful dash isn't functioning properly. Hopefully some can chime in.

Gears are in good condition? Any way to check if they're getting power? Think it's a related problem causing both of them to fail or separate issues? I can build a computer from scratch but I'm electronically retarded when it comes to these cars.

[dnguyen1963]

Your tach will not work with a bad SI board. Your speedo is another matter. You should take the cluster out, clean all the grounds well, tighten up the ground nuts, and check for crack in solder joins.

[Gregs///M]

Tach signal comes from the ECM and routes directly into the SI board, then to the tach gauge. Since it does not work, I would assume your SI batteries are dead.

Replace SI batteries first, then move onto the speedometer.

If speedo continues to not work with new batteries, check for speed signal.

Or you can check signal inputs to the cluster first if you want.
Speedometer signal (white connector) brown/red wire.
Tach signal (blue connector) black wire.

These wires should should 1.5-6 volts AC while wheels are moving (speed) and while engine is revving (tach.)

Give me a holler if you need SI batteries, I have new ones in stock.