is torque management for auto's only or is it programed in 6speeds too??

 

Autos only

 

ther's a TM table in the 6 speeds PCM; but it is only activated with the "Abuse Mode" ; which no one has ever been able to duplicate the conditions that the Abuse Mode is supposed to be for.

 

I get a C1276 every time I do an aggressive up-shift on my MN6 car, not from 1st though. It started happening after my CAI and Corsa install... I find it extremely hard to believe that those upgrades did anything even remotely close to changing the car's torque. Could this be linked to the mysterious "abuse mode"?

 

Not to hijack the thread or anything, but I was getting big-time knock retard on my 1-2 and 3-4 shifts at the track last fall (MN6 with headers/intake only). There were no trouble codes showing in the log files, just a lot of KR. I was wondering if it had anything to do with abuse mode or TM.

 

Your problem could very well be related to the TM tables as Headers will increase the car's torque, whether it changes it enough to affect any of the pre-programmed tables, I don't know... Hopefully someone with more brains them me on this step in. I'll see what I can find out in my maintenance DVD.

I was never concerned about mine, because it never affected the car in anyway other then throwing that code... But I'm getting my headers and X pipe tomorrow so I should learn something about it...

 

Not related to any fictitious abuse mode. C1276 has to do with the EBCM/EBCTM and the response it gets from the PCM after it sends a requested torque signal to the PCM. The code sets if there is no signal or the signal is out of range. This code will shut down your TC/Active Handling.

Bill

 

Hmmm so I have an underlying problem??? Any suggestions on where to look to resolve it?

What are you doing up so late? I don't think I've seen you on here so late before.

 

Didn't realize it was this late. There could be a bad ground or damaged wire somewhere. My 97 used to throw this code all the time when under acceleration until GM replaced the original EBTCM which had a hardware design flaw in it.

Here is the description of how the system works:

DTC C1276, P1644, or P1689
Circuit Description
The EBCM and the PCM simultaneously control the traction control. The PCM reduces the amount of torque supplied to the drive wheels by retarding spark timing and selectively turning off fuel injectors. The EBCM actively applies the brakes to the front wheels in order to reduce torque.

The EBCM sends a requested torque message via a pulse width modulated (PWM) signal to the PCM. The duty cycle of the signal is used to determine how much engine torque the EBCM is requesting the PCM to deliver. Normal values are between 10 and 90 percent duty cycle. The signal should be at 90 percent when traction control is not active and at lower values during traction control activations. The PCM supplies a pull up voltage of 5 volts that the EBCM switches to ground to create the signal.

The PCM sends a delivered torque message via a pulse width modulated (PWM) signal to the EBCM. The duty cycle of the signal is used to determine how much engine torque the PCM is delivering. Normal values are between 10 and 90 percent duty cycle. The signal should be at low values (around 10 percent) at idle and higher values under driving conditions. The EBCM supplies a pull up voltage of 12 volts that the PCM switches to ground to create the signal.

When certain PCM DTCs are set, the PCM will not be able to perform the torque reduction portion of traction control. A serial data message is sent to the EBCM indicating that traction control is not allowed.

The following conditions can cause this concern:

An open in the delivered torque circuit.
An short to ground or voltage in the delivered torque circuit.
A wiring problem, terminal corrosion, or poor connection in the delivered torque circuit.
A communication frequency problem.
A communication duty cycle problem.
The EBCM is not receiving information from the PCM.
Loose or corroded EBCM ground or PCM ground.

Let me know what you find. I think I will get to bed before the sun comes up.

Bill