C1277
Requested Torque Signal Circuit Malfunction
EBCM
DTC C1277 or P0856 in Antilock Brake System
The electronic brake control module (EBCM) and the powertrain control module (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 10-90 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 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 10-90 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.
Conditions for Setting the DTC
C1276
One of the following conditions exists:
• The EBCM detects that delivered torque signal is out of the valid range.
• The EBCM does not receive the delivered torque signal.
Diagnostic Aids
The following conditions can cause this concern:
• An open in the delivered torque circuit
• A 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
Install a scan tool.
Start the engine.
With a scan tool, observe the Delivered Torque parameter in the DRP/ABS/TCS data list.
Does the scan tool display the specified value?
SOURCE: oem code p2716
It can all be explained here: http://matrixowners.com/tsb/T-TC014-06.pdf
BOTTOM LINE: TAKE IT TOYOTA BEFORE THE WARRANTY EXPIRES @ 80,000 MILES OR 8 YEARS OF OWNERSHIP.
I had mine taken care of today free of charge, and hassle free, thanks to the service crew at Condit's Toyota.
SOURCE: oem code p2716
Same issue.
There is a service bulletin on this. Toyota will replace computer. I have a 2007 Corolla S with 56,000 miles
SOURCE: service engine light is on in my 2004 Buick LaSabre
the service engine soon light means a fault has occurred in the engine or emission system's electronic controls, it has nothing to do with any service you did in most cases, there are over 150 problems that turn the light on, to find out what the problem may be go to any Kragen Auto or Autozone parts store and ask them to run a OBD 2 trouble code test, IT IS FREE. then post the code back here for us to look at, which is also FREE.
SOURCE: Misfire of cylinder 2 & 5 on 04 Buick LaSabre Custom
Ok this may be something smal that may be simple to fixs; your plugs are in the wrong cylinder?
Check Your gap size .060 (In thousandths of an inch)
Im not sure of the size of engine please look below for your make?
Fig. 3.8L VIN 1 Engine Firing order: 1-6-5-4-3-2 Distributorless ignition system
Fig. 3.8L VIN K Engine Firing order: 1-6-5-4-3-2 Distributorless ignition system
Fig. 3.8L (VIN 1 and L) Engines Firing order: 1-6-5-4-3-2 Distributorless ignition system
Fig. 3.8L (VIN K) Engine Firing order: 1-6-5-4-3-2 Distributorless ignition system
I hope that this help!
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