Engine Only Traction Control (EOTC)
Some vehicles may be equipped with an engine only traction control (EOTC) system. In order to achieve maximum traction, the EOTC system is designed to limit wheel spin by modulating engine torque when driving on slippery or loose surfaces. Engine torque modulation is achieved by regulating fuel and spark to the cylinders. This means that the traction control system is controlled by the PCM and not the ABS module. The only function of the ABS module in an EOTC system is to provide wheel speed information to the PCM along the HS-CAN bus. The PCM uses the wheel speed information to determine when traction control is needed. The traction control system indicator in the instrument cluster will flash during a traction control event and will illuminate without flashing if the system is inoperative due to DTCs or some other concern.
The traction control system can be disabled by pressing the traction control switch. Traction control system status is indicated by the traction control OFF indicator in the switch being illuminated and the message center (if equipped) displaying Traction Control Off. The traction control system will reset and return to normal operation when the ignition switch is cycled or when the traction control switch is pressed and released a second time during the same ignition cycle.
The traction control system is contained in the PCM and is configured when the PCM is configured. Refer to Programmable Module Installation in MODULE CONFIGURATION article.
When the traction control system activates, any of the following can occur:
- A small deceleration or a reduction in the acceleration of the vehicle
- The traction control indicator in the instrument cluster flashes