DRIVER CORRECTION DEVICES AND AIDS

Depending on the vehicle, this is composed of:

- anti-lock braking system (ABS);

- electronic stability program (ESC) with understeer control and traction control;

- emergency brake assist;

- hill start assistance.

Anti-lock braking system (ABS)

Under heavy braking, the ABS prevents the wheels from locking, allowing the stopping distance to be managed and keeping control of the vehicle.

Under these circumstances, the vehicle can be steered to avoid an obstacle whilst braking. In addition, this system can increase stopping distances, particularly on roads with low surface grip (wet ground etc.).

You will feel a pulsation through the brake pedal each time the system is activated. The ABS does not in any way improve the vehicle's physical performance relating to the road surface and road-holding. It is still essential to follow the rules of good driving practice (such as driving at a safe distance from the vehicle in front etc.).

Operating faults:

- © and x lit up on the instrument panel alongside messages “CHECK ABS”, “CHECK BRAKING SYSTEM” and “CHECK ESC”: ABS, ESC and emergency brake assist are deactivated. Braking is always enabled;

- x, D, © and ® lit up on the instrument panel alongside the message “BRAKING SYSTEM FAULT”: this indicates a fault in the braking system.

In both cases, consult an approved Dealer.

Electronic stability program (ESC) with understeer control and traction control

Electronic stability control ESC

This system helps you to keep control of the vehicle in critical driving conditions (avoiding an obstacle, loss of grip on a bend, etc.).

Operating principle

A sensor in the steering wheel detects the direction selected by the driver.

Other sensors throughout the vehicle measure the actual direction.

The system compares driver input to the actual trajectory of the vehicle and corrects the trajectory if necessary by controlling the braking of certain wheels and/or engine power. In the event that the system is engaged, indicator light  flashes on the instrument panel.

Understeer control

This system optimises the action of the ESC in the case of pronounced understeer (loss of front axle road holding).

Traction control

This system helps to limit wheelspin of the drive wheels and to control the vehicle when pulling away accelerating or decelerating.

Operating principle

Using the wheel sensors, the system measures and compares the speed of the drive wheels at all times and slows down their over-rotation. If a wheel is starting to slip, the system brakes automatically until the drive supplied becomes compatible with the level of grip under the wheel again.

The system also adjusts the engine speed to the grip available under the wheels, independently of the pressure exerted on the accelerator pedal.

Operating faults

When the system detects an operating fault the message “CHECK ESC” and warning light © and  appear on the instrument panel. In this case, the ESC and traction control system are deactivated.

Consult an approved dealer.

Disabling the traction control system

In some situations (driving on very wet ground: snow, mud, etc. or driving with snow chains fitted), the system may reduce the engine output to limit wheelspin.

Emergency brake assist

This system supplements the ABS and helps reduce vehicle stopping distances.

Operating principle

The system is for detecting an emergency braking situation. In this case, the braking assistance immediately develops maximum power and may trigger ABS regulation.

ABS braking is maintained as long as the brake pedal is applied.

Hazard warning lights switching on

Depending on the vehicle, these may light up in the event of sudden deceleration.

Braking anticipation

Depending on the vehicle, when you rapidly release the accelerator, the system anticipates the braking manoeuvre in order to reduce stopping distances.

When using the cruise control:

- if you use the accelerator, when you release it, the system may be triggered;

- if you do not use the accelerator, the system will not be triggered.

Operating faults

When the system detects an operating fault the message “CHECK BRAKING SYSTEM” appears on the instrument panel along with the © warning light.

Consult an approved dealer.

Hill start assistance

Depending on the gradient of the incline, this system assists the driver when starting on a hill. It prevents the vehicle from rolling backwards, depending on the slope, by automatically applying the brakes when the driver lifts his/her foot off the brake pedal to depress the accelerator pedal.

System operation

It only operates when the gear lever is in a position other than neutral (other than N or P for automatic transmissions) and the vehicle is completely stationary (brake pedal depressed)

The system holds the vehicle for approximately 2 seconds. The brakes are then gradually released (the vehicle will move according to the slope).