Got this problem with my LS swap build trying to ask around need to make it work.

I got a digital dash board from those guys http://intellitronix.com/camaro.html

Got it installed (had to carve out lots of plastic) when I hooked it up I found out that tach and speedo not working. Every other thing in new dash works.

The problem is the following: I connect the signal wires from my LS ECU that give tach and speed signals directly to the dash - not working. When I checked the dash on a V8 (my friends firebird) we connected it to the distributor. It picked up the signal and worked fine. My stock gauges WORK fine with my LS ECU. The signal for stock gauges goes like this.

- wire from ECU then it goes through a resistor board in the dash (if you ever saw the insides of the 92 dash it has 2 resistor boards inside for tach and speedo) then out of resistor board it comes out 4 wires - they are connected to the stock gauge - tach for example (which has 4 connectors) and it works.

Is there a way to make this thing? They claim it to be a stock replacement but it has 1 wire when stock gauges have 4. And they cant help me since the engineer that designed it - quit 6 months ago.

 

Still cant make it work....

 

Need to level shift the 5v signal from the LS PCM to a 12 volt signal for the dash. Use a NPN transistor (2N3904) and a few resistors for each signal.

RBob.

 

Thank you! How do I connect the NPN transistor (2N3904)?
it has 3 connectors I found few of those at the local radio shop. 2 are for signal output and input and one is for 12v input?

And how many resistors will I need? Just measure the output signal to get 12v?

 

Is this the way I should wire this?



Where do I put the resistors?

 

See the picture. The resistors are 1/4W, Two 10K ohms and one 1K ohm. That should work, I know it does when interfacing a DIS ignition module to the stock tachometer.

RBob.

 

Thanks!!!
Will give it a try on weekend and post here.

 

IT's ALIVE!!!

The tach works great! - Used your circuit and it worked right away.

But the speedo is still not working. I tried using the same circuit different ways on it but it does not work. The problem is that my stock speedo is not working ether now. Although I am not sure that it worked maybe I assumed it did since I saw the stock tach working and thought they both worked (could be like that not sure now).

Any ideas on how to make speedo work?

Can i take the speed signal somewere else maybe the trans itself?

Would appreciate any Ideas!!!!

 

What transmission is it? If it is the one from the LS1 engine may be able to use a Dokoda Digitial SGI5 box.

RBob.

 

It is the LS1 transmission. It is electronic. The signal from transmission comes out as 2 wires - don't think I can pick up a signal there. I found where it connects to the ECU, but I cant find which wire from the ECU gives the signal to dash. The wire that ends up at the dash seems to be broken (I think) when I test it it does not show any imulse with speed increase or not.

 

Try pin 50 on the PCM's red connector for the VSS feed to the dash.

RBob.