C1276

CIRCUIT DESCRIPTION
The Electronic Brake and Traction Control Module (EBTCM) and the Powertrain Control Module (PCM) simultaneously control the traction control. The PCM sends a DELIVERED TORQUE message via a Pulse Width Modulated (PWM) signal to the EBTCM confirming the delivered torque level for proper Traction Control System (TCS) operation. The EBTCM supplies the pull up voltage.

CONDITIONS FOR SETTING THE DTC
Ignition voltage is present and the PWM signal is out of range or no signal is received for 7 seconds

ACTION TAKEN WHEN THE DTC SETS
^ A DTC C1276 is stored
^ The TCS is disabled
^ The TRACTION OFF indicator is turned on
^ The ABS remains functional

CONDITIONS FOR CLEARING THE DTC
^ The condition for the Diagnostic Trouble Code (DTC) is no longer present and the scan tool clear DTC function is used
^ 50 ignition cycles have passed with no DTCs detected

DIAGNOSTIC AIDS
^ Thoroughly inspect the wiring and the connectors. Failure to carefully and fully inspect the wiring and the connectors can result in misdiagnosis. Misdiagnosis may cause replacement of parts without repairing the malfunction.
^ The following conditions are other possible causes for this malfunction:
- An open, a short to ground, or a short to voltage in CKT 464
- A communication frequency problem
- A communication duty cycle problem
- A wiring problem, terminal corrosion, or a poor connection in CKT 464
- The EBTCM is not receiving information from the PCM
^ If an intermittent malfunction exists, refer to Troubleshooting Procedures.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
4. This step checks for the proper duty cycle.
5. This step checks for the proper frequency.