ABS
ABS (anti-lock braking system) regulates the speed of all impellers to ensure optimal wheel slip when braking at the traction limit. This prevents the wheels from locking up and helps maintain vehicle steering efficiency.
On the front axle, the brake pressure is regulated separately for each wheel. At the rear axle, the brake pressure is modulated by a regulator. The regulator supplies the same pressure to both rear brakes, the level of which is determined by the wheel that has the worst grip. This ensures the stability of the rear axle on uneven roads.
ARM
The ARM function uses the brakes and the engine to stabilize the vehicle during sudden maneuvers that could cause it to roll over.
ABS module (anti-lock braking system) monitors the actions of the driver and the behavior of the vehicle by various signals received from the power unit, wheel speed sensors, steering angle sensor and yaw and lateral acceleration sensor. This data is compared with the model behavior and, if the vehicle behavior is considered dangerous, the ABS module (anti-lock braking system) reduces engine power or brakes one or more wheels to stabilize the vehicle and allow the driver to regain control of the vehicle.
When the ignition is on, the ARM function is always active, even if the DSC function is off.
CBC
CBC regulates brake pressure to exceed DSC and ABS thresholds (anti-lock braking system), counteracting the yaw moment that occurs when braking into a corner. CBC creates corrective torque by limiting brake pressure on one side of the vehicle.
DSC
DSC controls the brakes and powertrain to maintain vehicle lateral stability. When the ignition is on, the DSC function is always on unless it is turned off with the DSC switch. Even when the DSC function is disabled, vehicle maneuvers with excessive yaw or lateral acceleration may cause the function to be activated to stabilize the vehicle.
DSC improves safety during sharp manoeuvres, as well as understeer or oversteer that can occur when cornering. ABS module (anti-lock braking system) monitors the yaw and lateral acceleration of the vehicle, as well as steering wheel rotation, and based on this data selectively applies individual brakes and transmits signals to adjust the torque of the power unit in order to reduce understeer or oversteer.
In general: understeer, the inside wheels are braked to counteract the yaw movement towards the outside of the turn; during oversteer, the outer wheels are braked to prevent the rear of the vehicle from moving towards the outside of the curve.
ABS module (anti-lock braking system) monitors vehicle directional stability based on signals from wheel speed sensors, steering wheel angle sensor, and yaw and lateral acceleration sensor. The directional stability is compared with the saved set values and, in case of any deviation from the directional stability given, the ABS module (anti-lock braking system) intervenes in the operation of the braking system and activates the appropriate brakes. On vehicles with automatic transmission, during DSC function, the ABS module (anti-lock braking system) also sends signals to TCM (transmission control module) to prevent gear shifting. ABS module if needed (anti-lock braking system) also sends signals to the following modules:
- ECM (engine control module) to reduce engine torque
- Transfer case control module for changing the moment of locking the center differential.
- Rear differential control unit for changing the moment of locking the rear differential.
The DSC function has priority over differential lock torque setting requests from the system "terrain response".
EBD
EBD (electronic brake force distribution) limits the pressure in the brake mechanisms of the rear wheels. When the brakes are applied, the mass of the vehicle is shifted forward, which reduces the braking efficiency of the rear wheels. This can cause the rear wheels to slip and cause the vehicle to lose stability.
EBD (electronic brake force distribution) uses anti-lock braking system components to automatically optimize rear brake pressure before the anti-lock braking system is activated. EBD (electronic brake force distribution) only controls the rear axle brakes.
ETC
ETC attempts to optimize wheel traction by reducing engine torque or braking spinning wheels until wheel traction is restored.
ETC turns on when individual wheel speed exceeds vehicle reference speed (positive slip), and the brake pedal is not depressed. The slipping wheel is braked, which allows excess torque to be transmitted through the drive shafts to wheels that do not slip. ABS module if needed (anti-lock braking system) also transmits on the high-speed CAN bus (controller network) signal to ECM (engine control module) to reduce engine torque. A torque reduction request can be fast or slow: slow response requests a reduction in throttle angle (only for 4.0 l and 4.4 l); when the reaction is quick, the ignition is switched off (4.0 l and 4.4 l) or fuel cut (diesel engine 2.7 l).
When the DSC function is turned off with the DSC switch, the torque reduction function does not work.
On vehicles with automatic transmission, during the operation of the ETC function, the ABS module (anti-lock braking system) also sends signals to TCM (transmission control module) to prevent gear shifting.
EBA
EBA (emergency brake assist) assists in emergency braking by automatically applying maximum braking force. There are two situations in which the ABS module (anti-lock braking system) includes EBA (emergency brake assist): When the brake pedal is depressed very hard and when the brake pedal is pressed hard enough to activate the ABS (anti-lock braking system) for front brakes.
When the brake pedal is pressed hard, the ABS module (anti-lock braking system) increases hydraulic pressure in all brake mechanisms until it reaches the ABS activation threshold (anti-lock braking system), providing maximum braking force under current traction conditions. ABS module (anti-lock braking system) controls abrupt application of the brakes on signals from the brake light switch and pressure sensor in the HCU (hydraulic control unit). If the rate of increase in hydraulic pressure exceeds the set threshold when the brake is applied, the ABS module (anti-lock braking system) begins emergency braking.
If the brake pedal is pressed hard enough to activate the ABS (anti-lock braking system) for front brakes, ABS module (anti-lock braking system) increases the hydraulic pressure of the rear brakes to a level at which the ABS is activated (anti-lock braking system).
EBA (emergency brake assist) operates until the driver releases the brake pedal enough that the hydraulic pressure in the HCU (hydraulic control unit) has not fallen below the threshold level stored in the ABS module (anti-lock braking system).
EDC
EDC prevents wheel slip caused by any of the following:
- A sudden increase in engine torque when the accelerator pedal is pressed hard.
- Abrupt engagement of the clutch after downshifting on vehicles with a manual transmission.
- Downshifting with CommandShift™ on vehicles with automatic transmission.
If the ABS module (anti-lock braking system) detects the start of wheel slip without applying the brakes, it reports to the ECM (engine control module) high-speed CAN signal (controller network) with a request for a short-term increase in engine torque.
HDC
HDC uses the vehicle's braking system to change the vehicle's speed and accelerate it when driving downhill at low speed, and when driving in off-road conditions with poor traction. In general, all four brakes are supplied with the same pressure, however, the pressure of individual brakes can be changed by the ABS function (anti-lock braking system) and DSC to maintain vehicle stability. The HDC function is selected using the HDC switch on the center console. HDC operates in both high and low gears at vehicle speeds up to 50 kph.
On manual transmission vehicles, HDC can only be used in first and reverse high gears, and in all low gears. Once the vehicle starts moving, fully release the clutch pedal. Do not operate the vehicle with HDC enabled when the transmission is in neutral.
On automatic transmission vehicles, HDC can be used in D, R and high CommandShift 1 and D, R and all low CommandShift gears. In position D, the transmission control module automatically selects the most suitable gear. Do not operate the vehicle with HDC enabled when the transmission is in neutral.
The HDC function can be selected at speeds up to 80 km/h, but it is only activated below 50 km/h. If the HDC function is selected:
- At speeds up to 50 km/h, the HDC status indicator lights up continuously if a valid gear is selected and, on vehicles with a manual transmission, the clutch pedal is depressed.
- At speeds between 50 and 80 km/h, the HDC status indicator lamp flashes and, on models with a high-level instrument cluster, the message center display indicates that the speed is too high. For more information, please refer to the Information and Message Center (413-08 Information and Message Center). If the HDC switch is pressed when the vehicle speed is over 80 km/h, the HDC status indicator lamp will not illuminate and the HDC function will not be selected.
- When the speed reaches 80 km/h or more, the buzzer will sound and the HDC function will turn off. This will turn off the status indicator lamp and, on vehicles with a high-level instrument cluster, the instrument cluster message center display will indicate that the HDC function has been deactivated.
When the HDC function is enabled, the ABS module (anti-lock braking system) calculates the target speed and compares it with the actual vehicle speed. Then the ABS module (anti-lock braking system) controls the HCU (hydraulic control unit) in active braking mode, maintaining the set speed. During active braking as a result of the HDC function, the ABS module (anti-lock braking system) also supplies power to the HDC relay to turn on the brake lights. When you press the brake pedal during active braking, you may feel the pedal pulsing, but this is not a malfunction.
The set speed varies from minimum to maximum for each gear and stage, depending on the pedaling of the driver. If the driver does not press the pedals, the ABS module (anti-lock braking system) sets the default speed.
Set speed for low stage
| limit value | Speed, km/h | |||
| Broadcast | ||||
| Automatic transmission | Manual Transmission | |||
| 1, R | D, 2 to 6 | 1, R | 2 to 6 | |
| Default | 3,5 (2,19) | 6 (3,75) | 3,5 (2,19) | 6 (3,75) |
| Minimum | 3,5 (2,19) | 3,5 (2,19) | 3,5 (2,19) | 3,5 (2,19) |
| Maxim | 20 (12,5) | 20 (12,5) | 20 (12,5) | 20 (12,5) |
Target speed for higher stage
| limit value | Speed, km/h | ||
| Broadcast | |||
| Automatic transmission | Manual Transmission | ||
| 1, R | D | 1, R | |
| Default | 6 (3,75) | 10 (6,25) | 6 (3,75) |
| Minimum | 6 (3,75) | 6 (3,75) | 6 (3,75) |
| Maxim m | 20 (12,5) | 20 (12,5) | 20 (12,5) |
The set speed varies from the minimum to the maximum value depending on how the accelerator pedal is depressed.
Also, the set speed can be changed using the '+' and '-' buttons of the cruise control system (in the presence of). For more information refer to Speed Control (310-03A). For more information refer to Speed Control (310-03B).
When the set speed is changed, the ABS module (anti-lock braking system) limits deceleration and acceleration to -0.5 m/s2 and +0.5 m/s2 respectively.
On manual transmission models, set speed change is suspended during a gear change to avoid unwanted braking when the accelerator pedal is released to change gear. ABS module (anti-lock braking system) determines the gear shift according to the following data:
- Information about the selected gear, transmitted over the high-speed CAN bus (controller network).
- Accelerator pedal release speed.
- Clutch pedal condition.
To ensure a safe transition from active braking to disengagement of the brakes, the ABS module (anti-lock braking system) uses a soft-off strategy to gradually release braking force if any of the following conditions are detected during active braking:
- The HDC function is disabled with the HDC switch.
- Malfunction of the node used by the HDC, which is not critical to the soft-off function.
- Depressing the accelerator pedal when the transmission is in neutral.
- Overheating of the brakes.
If soft shutdown is initiated as a result of a function shutdown or a component failure, the HDC function is disabled by the ABS module (anti-lock braking system). If soft shutdown is initiated by depressing the accelerator pedal while the transmission is in neutral, or if the brakes overheat, the HDC function remains in standby mode and resumes when the accelerator pedal is released or the brakes cool.
The soft-off strategy increases the set speed at a constant acceleration of 0.5 m/s2 until the maximum set speed is reached or until active braking is required within 0.5 s. If the accelerator pedal is in the range affecting the set speed, the acceleration is increased to 1.0 m/s2.
If a soft shutdown is initiated as a result of a part failure, a warning chime will sound and the HDC status indicator light will turn off. HDC Malfunction Indicator Lamp Turns On (for models with low level instrument cluster), or the message center display shows a fault message (for models with high level instrument panel).
If soft shutdown is initiated as a result of overheating of the brakes on a vehicle with a high instrument cluster, a message indicating that the HDC function is temporarily unavailable is displayed. On vehicles with a low level instrument panel, the HDC malfunction indicator lamp flashes. When the soft shutdown is completed, the HDC status indicator lamp will flash. The indicators continue to flash and/or the message remains displayed while the HDC function is selected until the brakes have cooled down.
To control the overheating of the brakes, the ABS module (anti-lock braking system) controls the duration of the brakes and on the basis of it calculates the temperature of each brake mechanism. If the calculated temperature of any brake mechanism exceeds the set value, the ABS module (anti-lock braking system) initiates soft shutdown. At the end of the soft shutdown cycle, the HDC function is enabled again when the ABS module (anti-lock braking system) determines that the temperature of all brake mechanisms does not exceed 64% of the limit value.
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