Circuit Description

Optimum vehicle stability enhancement system (VSES) function is depended on many variables. The characteristics of a specific vehicle, that affect vehicle handling or input signals to the electronic brake control module (EBCM), ultimately determine how the VSES operates. The basic EBCM software must be fine tuned as the vehicle is operated. This logic is referred to as adaptive learning.

Adaptive learning is accomplished by maintaining a yaw rate sensor/lateral accelerometer data table in the EBCM memory. As the vehicle is operated, the table is populated with data that is later referenced, and sometimes modified, to allow the EBCM to provide the best possible stability control for the specific vehicle.

A replacement EBCM may have some unreliable data stored in the yaw rate sensor/lateral accelerometer data table. For this reason, it is important to perform the yaw rate reference table reset procedure after replacing the EBCM.

Replacement of the yaw rate sensor/lateral accelerometer or the installation of different size tires may also the data stored in the table to become unreliable. Therefore, the yaw rate reference table reset procedure must be performed

This procedure is to be used only for vehicles equipped with VSES (JL4).

1. Turn OFF the ignition.
2. Disconnect the yaw rate sensor/lateral accelerometer harness connector.
3. Start the engine.
4. Apply firm and steady pressure to the brake pedal for at least 10 seconds.
5. Turn OFF the ignition.
6. Reconnect the yaw rate sensor/lateral accelerometer harness connector.
7. Turn ON the ignition and use the scan tool to clear the DTCs.