Traction Control is simultaneously controlled by the EBTCM and the Powertrain Control Module (PCM). 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 operation. The EBTCM supplies the pull up voltage.
DTC C1276 can be set anytime when ignition voltage is present. A malfunction exists if the PWM signal is out of range or no signal is received for a period of 7 seconds.
• | A malfunction DTC is stored. |
• | TCS is disabled. |
• | Traction Control (TRAC OFF) indicator is turned on. |
• | Service Vehicle Soon Indicator is turned on. |
• | ABS remains functional. |
• | Condition for DTC is no longer present and scan tool clear DTC function is used. |
• | 100 ignition cycles have passed with no DTCs detected. |
• | Possible causes for DTC C1276 to set are: |
- | Delivered Torque line (CKT464) open. |
- | Delivered Torque line (CKT464) shorted to ground. |
- | Delivered Torque line (CKT464) shorted to voltage. |
- | Communication frequency malfunction. |
• | It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. |
• | If an intermittent malfunction exists refer to Intermittents and Poor Connections Diagnosis in Wiring Systems. |
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | ||
2 |
Is the resistance within the range specified in the Value(s) column? | 0-2 ohms | ||
3 | Repair CKT 464 for an open or high resistance. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
4 |
Is CKT 464 shorted to ground? | -- | ||
5 | Repair CKT 464 for a short to ground. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
6 |
Is any voltage present on CKT 464 with the ignition ON? | -- | ||
7 | Repair CKT 464 for a short to voltage. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
8 |
Is the voltage within the range specified in the Value(s) column? | 4.5-5.5 V | ||
9 | Replace the EBTCM. Refer to Electronic Brake Control Module/Electronic Brake and Track Control Module Replacement . Is the replacement complete? | -- | -- | |
10 | Suspect the PCM. Refer to Powertrain On Board Diagnostic (OBD) System Check or Powertrain On Board Diagnostic (OBD) System Check in Engine Controls. Is the diagnosis complete? | -- | -- |