Mercedes-Benz GLK-Class: Driving safety systems

Mercedes-Benz GLK-Class / Mercedes-Benz GLK-Class 1st Gen Owner's Manual / Safety / Driving safety systems

Driving safety systems overview

In this section, you will find information about the following driving safety systems:

ABS (Anti-lock Braking System)
BAS (Brake Assist System)
ESP® (Electronic Stability Program)
EBD (Electronic Brake force Distribution)

Important safety notes

WARNING

The following factors increase the risk of accidents:

Excessive speed, especially in turns
Wet and slippery road surfaces
Following another vehicle too closely

The driving safety systems described in this section cannot reduce these risks or prevent the natural laws of physics from acting on the vehicle. They cannot increase braking or steering efficiency beyond that afforded by the condition of the vehicle brakes and tires or the traction afforded.

Only a safe, attentive, and skillful driver can prevent accidents.

The capabilities of a vehicle equipped with the driving safety systems described in this section must never be exploited in a reckless or dangerous manner which could jeopardize the user's safety or the safety of others.

Always adjust your driving style to the prevailing road and weather conditions and keep a safe distance to other road users and objects on the street.

If a driving system malfunctions, other driving safety systems may also switch off. Observe indicator and warning lamps that may come on as well as messages in the multifunction display that may appear.

Please note that the driving safety systems described only work as effectively as possible when there is adequate contact between the tires and the road surface. Pay particular attention to the information regarding tires, recommended minimum tire tread depths etc. in the "Wheels and tires" section ().

In wintry driving conditions, always use winter tires (M+S tires) and if necessary, snow chains. Only in this way will the driving safety systems described in this section work as effectively as possible.

ABS (Anti-lock Braking System)

Important safety notes

Observe the "Important safety notes" section ().

ABS regulates brake pressure in such a way that the wheels do not lock when you brake. This allows you to continue steering the vehicle when braking.

ABS works from a speed of about 5 mph(8 km/h) upwards, regardless of roadsurface conditions. ABS works on slippery surfaces, even when you only brake gently.

WARNING

If the ABS malfunctions, other driving systems such as the BAS or the ESP® are also switched off. Observe indicator and warning lamps that may come on as well as messages in the multifunction display that may appear.

If the ABS malfunctions, the wheels may lock during hard braking, reducing the steering capability and extending the braking distance.

The warning lamp in the instrument cluster lights up when the ignition is switched on. It goes out when the engine is running.

Braking

If ABS intervenes when braking, you will feel a pulsing in the brake pedal.

If ABS intervenes: continue to depress the brake pedal with force until the braking situation is over.
To make a full brake application: depress the brake pedal with full force.

The pulsating brake pedal can be an indication of hazardous road conditions, and functions as a reminder to take extra care while driving.

WARNING

Do not pump the brake pedal. Use firm, steady brake pedal pressure instead. Pumping the brake pedal defeats the purpose of the ABS and significantly reduces braking effectiveness.

BAS (Brake Assist System)

Observe the "Important safety notes" section ().

BAS operates in emergency braking situations. If you depress the brake pedal quickly, BAS automatically boosts the braking force, thus shortening the stopping distance.

Keep the brake pedal firmly depressed until the emergency braking situation is over. ABS prevents the wheels from locking.

The brakes will function as usual once you release the brake pedal. BAS is deactivated.

WARNING

If the BAS malfunctions, the brake system still functions, but without the additional brake boost available that the BAS would normally provide in an emergency braking maneuver. Therefore, the braking distance may increase.

ESP® (Electronic Stability Program)

Important safety notes

See the "Important safety notes" section ().

If ESP® detects that the vehicle is deviating from the direction desired by the driver, one or more wheels are braked to stabilize the vehicle. If necessary, the engine output is also modified to keep the vehicle on the desired course within physical limits. ESP® assists the driver when pulling away on wet or slippery roads. ESP® can also stabilize the vehicle during braking.

If ESP® intervenes, the ESP® warning lamp flashes in the instrument cluster.

WARNING

Never switch off the ESP when you see the ESP warning lamp flashing in the instrument cluster. In this case proceed as follows:

When driving off, apply as little throttle as possible.
While driving, ease up on the accelerator pedal.
Adapt your speed and driving style to the prevailing road conditions.

Failure to observe these guidelines could cause the vehicle to skid. The ESP cannot prevent accidents resulting from excessive speed.

Vehicles without 4MATIC: switch the ignition off when:

the parking brake is being tested using a dynamometer
the vehicle is being towed with the front/ rear axle raised

Application of the brakes by ESP® may otherwise destroy the brake system.

Vehicles with 4MATIC: switch off the ignition when the parking brake is being tested on a brake dynamometer. Application of the brakes by ESP® may otherwise destroy the brake system.

Vehicles with 4MATIC: function or performance tests may only be carried out on a 2-axle dynamometer. If you wish to operate the vehicle on such a dynamometer, please consult an authorized Mercedes-Benz Center in advance. You could otherwise damage the drive train or the brake system.

Only use wheels with the recommended tire sizes. Only then will ESP® function properly.

ETS/4ETS (Electronic Traction System)

WARNING

Observe "Important safety notes" ().

Traction control is part of ESP®.

Traction control brakes the drive wheels individually if they spin. This enables you to pull away and accelerate on slippery surfaces, for example if the road surface is slippery on one side. On vehicles with 4MATIC, more drive torque is also transferred to the wheel or wheels with traction.

Traction control remains active if you deactivate ESP®.

Deactivating/activating ESP®

Observe the "Important safety notes" section ().

WARNING

ESP® should not be deactivated during normal driving other than in the circumstances described below. Disabling the system will reduce vehicle stability in driving maneuvers.

Do not deactivate ESP® when the emergency or spare wheel is mounted.

ESP® is activated automatically when the engine is started.

It may be best to deactivate ESP® in the following situations:

when using snow chains
in deep snow
on sand or gravel

WARNING

Switch on ESP® immediately if one of the previously stated conditions is no longer met. Otherwise, ESP® cannot stabilize the vehicle if it begins to lurch or when a wheel spins.

When you deactivate ESP®:

ESP® no longer improves driving stability.
the engine's torque is no longer limited and the drive wheels can spin. The spinning of the wheels results in a cutting action, which provides better grip.
traction control is still activated.
ESP® still provides support when you brake.

If ESP® is deactivated and one or more wheels start to spin, the ESP® warning lamp in the instrument cluster flashes. In such situations, ESP® will not stabilize the vehicle.

To deactivate: press button 1. The ESP® OFF warning lamp in the instrument cluster lights up.

WARNING

When the ESP OFF warning lamp lights up, ESP is switched off.

When the ESP warning lamp and the ESP OFF warning lamp are on continuously, ESP is not operational due to a malfunction.

When ESP is switched off or not operational, the vehicle's stability during standard driving maneuvers is reduced.

Adapt your driving style to suit the prevailing road conditions/weather conditions and to the non-operating status of ESP.

Avoid spinning the driven wheels for an extended period with ESP® deactivated. You could otherwise damage the drivetrain.

To activate: press button 1. The ESP® OFF warning lamp in the instrument cluster goes out.

ESP® trailer stabilization

If your vehicle with trailer (vehicle/trailer combination) begins to lurch, you can only stabilize the vehicle/trailer combination by depressing the brake firmly.

In this situation, ESP® assists you and can detect if the vehicle/trailer combination begins to lurch. ESP® slows the vehicle down by braking and limiting the engine output until the vehicle/trailer combination has stabilized.

Trailer stabilization is active from a speed of approximately 40 mph(65 km/h).

WARNING

The system will not be able to assist when the trailer jackknifes

if the ESP® has switched off due to a malfunction
on wet or icy roads
on roads with slippery surface
in sand or gravel

Trailers with a high center of gravity may tip over before the system recognizes swaying of the trailer.

Trailer stabilization does not work if ESP® is deactivated or disabled because of a malfunction.

EBD (electronic brake force distribution)

Observe the "Important safety notes" section ().

EBD monitors and controls the brake pressure on the rear wheels to improve driving stability while braking.

WARNING

If EBD has malfunctioned, the braking system remains available with full brake boosting effect. However, the rear wheels can still lock, e.g. under full braking. This could cause you to lose control of your vehicle and cause an accident. You should therefore adapt your driving style to the different handling characteristics.