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Normal Operation

PURPOSE
The Enhanced Traction System (ETS) is designed to limit wheel slip during acceleration.

OPERATION
This objective is accomplished by cutting fuel to selected cylinders, retarding spark and upshifting the transmission.

The Electronic Brake Control Module (EBCM) - monitors wheel speed slip through the ABS wheel speed sensors and determines the desired torque reduction needed to minimize wheel spin. The torque reduction the EBCM requests may result in a combination of fuel cutoff, spark retard, and upshifting the transmission, depending on the torque reduction required. This request is sent from the EBCM through the serial data link to the Powertrain Control Module (PCM).

The PCM Calculates - and employs fuel cutoff and spark retard values to achieve the requested engine torque. If the EBCM determines that the engine torque reduction is not suffrcient to minimize wheel spin, it will request a transmission upshift.

The ETS Will Be Enabled - when the ETS switch is in the ON position (ETS OFF indicator not illuminated), the engine coolant temperature is within normal operating range and the manifold air temperature is within normal operating range.