Traction control requested torque on a conversion

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Jan 31, 2021 | 06:51 PM

ssjimmyss

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Traction control requested torque on a conversion

It has been a long time since I have visited the forum but I am back in the middle of a new swap. I have just finished up installing a 07 tbss ls2/4l70e/e67 into a 2006 hummer h3 that originally had a 3.5l I5. I used hptuners to turn off vats, a couple fan codes, adjust for 37" tires and 5.13 gears but otherwise it is still a factory tbss tune. I reused tbss sensors, induction exhaust to keep things simple.
I have two issues that I could use some help on and I hope that someone here might have some experience with..

stabilitrac and traction control errors are showing on the dic. I am setting a p0856 tcs requested torque dtc. As I understand it this is the requested torque from the electronic brake control module for the tcs operation. I cannot see if the corresponding c code is setting with hptuners but I assume this is what is From the service manual I see this should be a 5v pwm signal from the tbss ebcm representing 30 to 90% torque reduction. Diagnostic limits seem to be set between 5 and 95%. The hummer h3 ebcm seems to default to 99.2% and even after I change the tbss diag limits in hptuners to 0 and 200% I am still occasionally setting the p0856 code. The service manual for the hummer h3 also says its ebcm uses a 5v pwm signal for its requested torque but doesn't provide more detail. Has anyone had experience trying to get this pwm requested torque signal to work on a conversion? I would like to keep traction control and stabilitrac functional if possible.
The other concern i have is the tbss is full time awd but I kept my h3's selectable 4wd transfer case with unique 4:1 low gear. I am not sure how the tbss system reacts to a 4 low gear. I have tried it briefly in my driveway and it seems fine at low speed, but I am not sure if there is something special I need to do. The vss is located at the back of the tcase for both applications.

thanks in advance

Last edited by ssjimmyss; Jan 31, 2021 at 06:58 PM.

Jan 31, 2021 | 07:34 PM

Fang

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You were told how to fix this over at HPT and didn't like the answer (which was: program the ECM with a 2008 H3 operating system). The TBSS OS is not compatible with the H3's EBCM. A '08 H3 OS will be compatible with the '06 H3 EBCM.

Jan 31, 2021 | 07:51 PM

ssjimmyss

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Quote:

Originally Posted by Fang

Thanks, it is not a matter of me liking or not liking a suggestion there, I am trying to learn more about how the pwm signal works and why it is not compatible. If it makes you feel better I am also pursuing getting a new pcm and starting with a 08 h3 5.3 tune but that brings its own issues that I don't want to get into here. Even if I get that to work I am still curious what is actually different between the os and why it doesn't work. Someone on the internet just saying it isn't compatible doesnt satisfy my curiosity

, I wish it did.

Jan 31, 2021 | 08:28 PM

Fang

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So educate yourself on how to reverse engineer the raw hex of the two operating systems and figure out what's different between them. My guess is if you were up to that kind of challenge you'd have done it already. I know I'm not. I'm just a dumb ex-dealership tech.

A bone-stock 2008 H3 with a 2008 H3 ECM and 2008 H3 EBCM has working traction control with no error messages, yes? So copy what the factory did.

Dec 19, 2021 | 12:59 PM

draciel882

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I really don't want to revive this thread but I am having the same issue. 06 H3. I flashed an e67 to 08 H3 5.3L file using SPS and I'm getting codes for both delivered and requested torque for the traction control. I have an AR5 swapped in but I have the wires run to the ECM from the EBCM as they should be according to the wiring diagram from the 08 Hummer. Any ideas of the solution to this? Also ssjimmyss, if you are in need of an 08 H3 ecm, I have a spare.

Dec 19, 2021 | 01:26 PM

ssjimmyss

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Quote:

Originally Posted by draciel882

I havent gotten any further with this on my project. Is your code and traction light setting immediately on startup or after a drive maneuver that uses traction control? Have you played with the tcs options in hptuners? Others have done what you did and got it to work so there must be a way with your setup. Let me know how much you want for your ecm, I can see if I can get it to work with my setup and see if I can help you diagnose.

Dec 19, 2021 | 01:30 PM

draciel882

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I haven't played with any of the TCS options in HP Tuners. They aren't there on a manual swap file. I'm considering to put the file back to auto and a deleting all the codes related to auto trans. Not sure that will get me where I want to be. Shoot me a message on ecm. I'm sure we could work something out.