Traction Control System

When drive wheel slip is noted while brake is not applied, EBCM will enter traction control mode.

First, EBCM requests PCM to reduce amount of torque to drive wheels via requested torque signal circuit. PCM reduces torque to drive wheels by retarding spark timing and turning off fuel injectors. PCM reports amount torque delivered to drive wheels via delivered torque signal circuit.

If engine torque reduction does not eliminate drive wheel slip, EBCM will actively apply drive wheel brakes. During traction control braking, hydraulic pressure in each drive wheel circuit is controlled to prevent drive wheels from slipping. Master cylinder isolation valve closes in order to isolate master cylinder from rest of hydraulic system. Prime valve then opens to allow pump to accumulate brake fluid to build hydraulic pressure for braking. Drive wheel inlet and outlet solenoid valves then open and close in order to perform pressure hold, pressure increase and pressure decrease.