sumyunguy

I have a new installation of a LS3 in a 2003 S10. The ECU is an E67 from a 2011 Cadillac CTS-V (Operating System 12639469). The engine runs acceptably (although it does need a tune). The problem is with my gauges. The fuel and ECT gauges do not work. The low fuel light and battery warning is on. Oil pressure and volt meter gauges work. The 2003 S10 uses Class 2 serial data to run the problematic gauges.

The wiring harness, ECU, etc was purchased from Current Performance and provided as an entire unit. I have contacted them several times and so far the most effective reply has been:

The serial data would be easy to check with an older OBD2 scanner that can read Serial data instead of CAN Bus. Plug that in to your OBD port and see if it is able to read the data stream to the computer. Otherwise, you can pull the cluster and do a continuity test with the wiring from the cluster to the ECU. The Blue connector on the computer, pins 15 and 16 are the class 2 serial data.

I checked continuity of the Dark Green wire in pin 16 on the ECU to the splice pack and it is good. I borrowed a GM Tech 2 scanner from a friend and was able to ping all modules and was able to sweep the gauges. (I am assuming that this means I have connectivity to the gauge cluster). The Tech 2 also indicates that the gauges are not receiving any input from the ECU.

I can see ECT and Fuel information using HPtuners.

I was able to get a copy of the 2011 CTS-V pinouts and it indicates pins 14-17 are not used.

Now here are my questions

• Is it possible that Class 2 serial data is not "enabled" on this particular OS, since it is not used?
• If that is the case, how do I enable it?
• If not, is it possible the ECU is sending degraded serial data, or perhaps, not sending at all?
• Am I missing something in my diagnostics?

I have been beating my head against a wall trying to resolve this, so thanks in advance for any help and sorry for the wall of text.

Bob

MontecarloDrag

iTrader: (3)

Gen4 ECMs don't have a low speed/class 2 data bus, they only have the high speed CAN bus (GMLAN).
To have a Class 2 bus in a vehicle, a BCM is used (Body Control Module).
So, if you have a E67 without a BCM you won't be able to use a stock instrument cluster since it doesn't speak CAN, only Class-2
I don't know if the 2003 cluster will handle the serial messages from a 2011 class-2 bus, some gauges may not work. It will talk to the other modules in the truck tho

sumyunguy

Thanks for the feedback. I suppose I need to talk to the vendor about why they would supply me with an ECU they know would not work with my application. I will also try some other tests (lab scope) to verify that is case.

Thanks again.

Bob

MontecarloDrag

iTrader: (3)

To be fair, you don't have any choice, unless you want to run your LS3 using a Gen3 controller with a 58x to 24x converter box. It is possible (I have done it) and the Gen3 PCM would easily run your gauges. However, using a Gen3 PCM in a LS3 is a step backwards IMO .

What I would do to have gauges is source a BCM from same vehicle (sorry I said VCIM, the correct module is BCM), hook it to power, ground and feed it the CAN BUS wires, don't forget to properly terminate the can network with a resistor.
This will create a Class-2 bus. Then hook the cluster and other modules to it. It may not work for everything.