Is there anyone that can help w/EPS install?

[Kenny]

Hey guys, I am desperately looking for help with an electric assist power steering install. I have a Cobalt SS column available and am in need of knowledge of how/where to pick up the proper data inputs. I am willing to use whatever ECM, or ECM/BCM combo necessary. This is for a LS powered/AWD S-10.......I have nothing except for unnatural determination at this point.

Any input would be greatly appreciated.....except:"don't do it", or "you need this $3000+ kit"

Thanks guys :thumbsup:

[MyToyZ]

If you can get it to work I think you'll be happy with it. To the best of my knowledge you will need a BCM from a similar vehicle that you obtained the column from because the BCM contains the base maps for different amounts of assist when needed. Will the PSCM function without these maps? Probably but in default mode. The system also needs a speed signal from the PCM for varying assist with speed. The last module would be the IPC but this is used for message display only. All data is sent over the serial data line between modules. Trying to find modules and calibrations that will communicate may be the hardest part. I do not know of any LS engines using EPS until 2013 Camaros but that is with the new belt type system. I've worked on these systems quite abit in factory applications but never adapted one for aftermarket use. Good luck.

[Kenny]

Thank you so much for your input and encouraging thoughts. The BCM is what I need to figure out fer sure. I was under the impression that the steering assist was determined by the programming in the module that is mounted on the motor, but that needs input from the CAN bus system......??? You have given me approximately 138.2% more knowledge than I already had :thumbsup: Is there any kind of reference material? I am completely obsessed with making this work.

Once I found a independent front suspension differential to swap into this project that has every kind of posi available including torsen gear type..... I just assumed that was the car gods giving me the green light on all of my unrealistic goals :D

[MyToyZ]

CAN-bus is the type of data line modules use to communicate. Messages are sent between different modules on a pair of wires instead of all modules being hard wired to sensors. In other words, for example, the speed sensor info is used by many modules, IPC for speedo, ECM for fuel and ignition, TCM for shift points, or in your case the PSCM for steering feel. Having a single module pickup the data from a sensor it can then send that info on to other modules that need it over the data line. The problem you may run into as I briefly mentioned in my first post is that when vehicles are built, the modules are calibrated to send and receive data to and from other modules, so they are always looking for each other on the data line. Using just the ECM, PSCM, and BCM in your case may not be sufficient to make the system work as designed if another module needs to contribute something to the data stream. I'm not trying to scare you I'm just trying to give you the best info as I know it.

[exwestracer]

Unfortunately, the OEM thinks about a lot of things we DON'T when we are trying to use this technology in a performance build. I took a class in advanced GM body electrics a couple of years ago, and BOY was it ever an eye-opener...

Here are some inputs that the BCM might be looking for in order to make decisions about power steering assist.

Vehicle speed (obvious)
Steering wheel angle
Gear position
AWD engaged
Headlights on
Wipers on
Ambient temperature
No.of occupants (air bag seat weight sensors)
ABS engaged
etc., etc., etc.

To the OEM, it's no big deal to pool all this data, because it's coming in for various other reasons as well. But, as mentioned above, if all the data parameters are NOT present, the BCM will simply go into a default mode, so the EPS will not work as designed anyway.

I'm NOT telling you not to do it, just trying to help you understand that we can't just think in terms of "I need this box, that box, and a motor" anymore...

[Kenny]

I know that's right, and let's not forget the radio..... I had a stereo shop when the first harnesses came out to keep the GM air bags functional when replacing the head unit. I talked to my nephew that has been through a lot of the electronics training, and the opinion he expressed was that GM had the best communication system between all the different modules and it may be as easy as picking compatible years. He did not know this for sure......but he did indicate that the GM system would be the most reasonable one to work with by far.

I guess the reasonable thing to do is start with the computer out of the Cobalt and see if it is the same basic model as any of the V8 stuff, then work on pin out comparisons :bang: If that turns out favorably.... magnetic rheological shocks anyone?? :peepwall: