Hans Grüber

iTrader: (2)

I have an E38 and harness out of a 2010 Camaro.

When looking at the ECM pinouts I notice that all of the in gauge cluster info (RPM, oil pressure, voltage etc) is done through a single CAN/data wire, only the MIL/check engine light has its own pinout.

How are people getting tach and other signals?

rsz288

Aftermarket guages and or recalibrated ECM so it supports hardwire.

jpndave

The tach signal can be programmed in. The rest of the gauges will need different senders.

futureuser

iTrader: (1)

An aftermarket tach that can read a 1 cylinder 5 volt signal and you can use tap a single coil trigger. I have two tachs in my car that can read the signal. One is the dakota digital vhx gauge, the other is the NOS window switch. There is not a single rpm wire in the wiring with an E38, as you know. Both of my tachs can provide signal for a shift light.

If you have an electronic tach that can't do the 5v signal try this:

http://painlesswiring.com/webcatalog...rchField=60150

Painless 60150

The other signals, I'm using aftermarket sending units. There is a spare port in one of the cylinder heads for your temp sending unit, and I got rid of the computer oil pressure monitoring and used the factory oil pressure sending location for my aftermarket gauge sending unit. There are alternatives to this like using the oil cooler block of plate.

The aftermarket is catching up quick.

iroczracer07

iTrader: (1)

I'm just getting into an LS1 and you guys are already tearing up new camaros????? All I can say is....

1989GTA

"There is not a single rpm wire in the wiring with an E38"

I am learning to. Cannot J1-48 on the E38 ECM be programed to provide the tach signal?

71403

E38 tach output worked for me using an Express van OS, here is the writeup I used:

http://www.hptuners.com/forum/showthread.php?t=36611

bhop42

iTrader: (2)

Yep, I added 12v and a resistor just like above.

Goldhawg

iTrader: (7)

Can you clarify how you added 12v to your tach signal? Or is this just a separate 12v power to the tach itself? I have already wired in a pin connection to the J1-48 location on my ECM and I knew I might need a resister, but I didn't know about the 12v and how that works. Thx!!

bhop42

iTrader: (2)

Yes, just add a seperate 12v source. From above post:
"Correct HPTuners tach settings for E38 ecm with 58x crank sensor.
Tach Output = Crank
Resolution - High =14
Resolution - Low =15
This will make the ECM output the correct frequency for a 2 pulse per revolution tach. The Duty cycle of the frequency will be 48.3%. 14/29

Tach output is on Pin 48 of the black connector.
You need to add a resistor (about 1k ohm) between the tach output and 12V to Pull-Up the Output signal to a usable voltage for aftermarket tachs."

Jesus Freak

My GMPP controller kit has an e38 and it has pinouts for tach, oil pressure, tps and vss.
Look at wiring diagrams for an ls2 cts-v. Thats what my instructions say to use for diagnostics.

futureuser

iTrader: (1)

Things have come a long way in a little over a year that I've been up and running. I stand corrected.

71403

What year CTS-V got the E38? Alldata shows a 3 connector ECM (E40?) for '06 & '07

I'm running a DRAC/VSSB in parallel with the T42 on my 4l80e to get a 4k ppm output for the speedo, would love to get a 4k ppm output from the E38.

Goldhawg

iTrader: (7)

Ok, I'll try again w/o a PM and show my ignorance on the off chance someone else is also still confused. I had read the previous posts, but still isn't clear how you "add...12v to pull up output signal". Is this something done w/in the tuning process that I have my tuner do? Or do I need to find a 12v source to somehow wire into my tach or what?

Thx for your patience and help in educating me.

71403

2nd picture on this post

http://67-72chevytrucks.com/vboard/s...d.php?t=445975

1k resistor. One side to +12, one side to tach signal wire.

Haggar

This is the correct way to do it. Inside the OEM cluster, its how its done, except with a 680 ohm resistor. (the Camaro clusters were designed with the provision for a tach input, but the components are not placed, and the software doesn't support it)... lol, I designed the Camaro instrument cluster electronics.

tijoe

I don't know if anyone here has been reprogramming their 2010 Camaro ECMs, but on my engine conversion, I found out that 2010 and newer Camaros have Global "A" security enabled. All of the modules used in the Camaro send security information between them. If any one module is removed and the proper codes are not sent and received, then the car eventually wont start. All of this is controlled through the BCM (Body Control module). I converted my E38 to run like a 2009 Pontiac G8, GXP.

If you are going to run a stand alone LS3 using an E38 ECM, then you will need to get it reprogrammed so it will work.

Oh yeah, The instrument panel information is supplied through the BCM. The BCM processes the CAN messages sent from the ECM and forwards them to the Instrument panel. All the signal traffic Consists of CAN messages between the BCM and Instrument panel. There is not a direct link to the engine signals. As others have stated, you have to reprogram the ECM to be able to direct access the engine data. (They did this on the E-Rod harness and ECM for the LS3 from GM.

-TheBandit-

iTrader: (1)

If I remember correctly Dakota Digital came out with some kind of converter box that connects to the OBD port and drives conventional analog gauges. Might be worth a look.