Jeep Cherokee (KL): Brake Assist System (BAS). Hill Start Assist (HSA). Traction Control System (TCS)

Brake Assist System (BAS)

The BAS is designed to optimize the vehicle's braking capability during emergency braking maneuvers. The system detects an emergency braking situation by sensing the rate and amount of brake application and then applies optimum pressure to the brakes. This can help reduce braking distances. The BAS complements the anti-lock brake system (ABS). Applying the brakes very quickly results in the best BAS assistance. To receive the benefit of the system, you must apply continuous braking pressure during the stopping sequence, (do not "pump" the brakes). Do not reduce brake pedal pressure unless braking is no longer desired. Once the brake pedal is released, the BAS is deactivated.

WARNING!

The Brake Assist System (BAS) cannot prevent the natural laws of physics from acting on the vehicle, nor can it increase the traction afforded by prevailing road conditions. BAS cannot prevent collisions, including those resulting from excessive speed in turns, driving on very slippery surfaces, or hydroplaning.

The capabilities of a BAS-equipped vehicle must never be exploited in a reckless or dangerous manner, which could jeopardize the user's safety or the safety of others.

Hill Start Assist (HSA)

The HSA system is designed to mitigate roll back from a complete stop while on an incline. If the driver releases the brake while stopped on an incline, HSA will continue to hold the brake pressure for a short period. If the driver does not apply the throttle before this time expires, the system will release brake pressure and the vehicle will roll down the hill as normal.

The following conditions must be met in order for HSAto activate:

  • The feature must be enabled.
  • The vehicle must be stopped.
  • Park brake must be off.
  • Driver door must be closed.
  • The vehicle must be on a sufficient grade.
  • The gear selection must match vehicle uphill direction (i.e., vehicle facing uphill is in forward gear; vehicle backing uphill is in REVERSE gear).
  • HSA will work in REVERSE gear and all forward gears. The system will not activate if the transmission is in PARK or NEUTRAL. For vehicles equipped with a manual transmission if the clutch is pressed HSAwill remain active.

WARNING!

There may be situations where the Hill Start Assist (HSA) will not activate and slight rolling may occur, such as on minor hills or with a loaded vehicle, or while pulling a trailer. HSA is not a substitute for active driving involvement. It is always the driver's responsibility to be attentive to distance to other vehicles, people, and objects, and most importantly brake operation to ensure safe operation of the vehicle under all road conditions. Your complete attention is always required while driving to maintain safe control of your vehicle. Failure to follow these warnings can result in a collision or serious personal injury.

Towing With HSA

HSA will also provide assistance to mitigate roll back while towing a trailer.

WARNING!

  • If you use a trailer brake controller with your trailer, the trailer brakes may be activated and deactivated with the brake switch. If so, there may not be enough brake pressure to hold both the vehicle and the trailer on a hill when the brake pedal is released. In order to avoid rolling down an incline while resuming acceleration, manually activate the trailer brake or apply more vehicle brake pressure prior to releasing the brake pedal.
  • HSA is not a parking brake. Always apply the parking brake fully when leaving your vehicle.

    Also, be certain to leave the transmission in PARK.

  • Failure to follow these warnings can result in a collision or serious personal injury

Disabling And Enabling HSA

This feature can be turned on or turned off. To change the current setting, proceed as follows:

  • For vehicles equipped with the Electronic Vehicle Information Center (EVIC) or Driver Information Display (DID), refer to "Electronic Vehicle Information Center (EVIC)" or "Driver Information Display (DID)" in "Understanding Your Instrument Panel" for further information.
  • If disabling HSA using Uconnect Settings, refer to "Uconnect Settings" in "Understanding Your Instrument Panel" for further information.

For vehicles not equipped with the EVIC/DID, perform the following steps: 1. Center the steering wheel (front wheels pointing straight forward).

2. Shift the transmission into PARK.

3. Apply the parking brake.

4. Start the engine.

5. Rotate the steering wheel slightly more than one-half turn to the left.

6. Push the "ESC Off" button located in the lower switch bank below the climate control four times within twenty seconds. The "ESC Off Indicator Light" should turn on and turn off two times.

7. Rotate the steering wheel back to center and then an additional slighty more than one-half turn to the right.

8. Turn the ignition switch to the OFF position and then back to the ON position. If the sequence was completed properly, the "ESC Off Indicator Light" will blink several times to confirm HSA is disabled.

9. Repeat these steps if you want to return this feature to its previous setting.

Traction Control System (TCS)

This system monitors the amount of wheel spin of each of the driven wheels. If wheel spin is detected, the TCS may apply brake pressure to the spinning wheel(s) and/or reduce engine power to provide enhanced acceleration and stability. A feature of the TCS, Brake Limited Differential (BLD), functions similar to a limited slip differential and controls the wheel spin across a driven axle. If one wheel on a driven axle is spinning faster than the other, the system will apply the brake of the spinning wheel. This will allow more engine torque to be applied to the wheel that is not spinning. BLD may remain enabled even if TCS and ESC are in a reduced mode.

    Previous pageBrake System Warning Light. Anti-Lock Brake System (ABS). Anti-Lock Brake Warning Light

    Brake System Warning Light The red "Brake SystemWarning Light" will turn on when the ignition switch is turned to the ON position and may stay on for as long as four seconds. If the "Brake System ...

    Next pageElectronic Stability Control (ESC)

    This system enhances directional control and stability of the vehicle under various driving conditions. ESC corrects for oversteering or understeering of the vehicle by applying the brake of the ap ...

    Other materials:

    Removal and installation
    Speed control servo REMOVAL (1) Disconnect negative battery cable at battery. (2) Disconnect vacuum line at servo (Fig. 1). (3) Disconnect electrical connector at servo. (4) Disconnect servo cable at throttle body. Refer to Servo Cable Removal/Installation. (5) Remove 2 mounting nuts h ...