New brake pads
New brake pads do not give full braking effect for the first 400 km, they must first be “bedded in”. However, you can compensate for the slightly reduced braking effect by applying more pressure on the brake pedal. Avoid placing a heavy load on the brakes during the running-in period.
On vehicles with ceramic brake discs* this distance could be considerably longer. However, you can compensate for the slightly reduced braking effect by applying more pressure on the brake pedal. Avoid placing a heavy load on the brakes during the running-in period.
Wear
The rate of wear on the brake pads depends a great deal on how you drive and the conditions in which the vehicle is operated. Negative factors are, for instance, city traffic, frequent short trips or hard driving with abrupt starts and stops.
Noises
Brake noise may develop in certain situations, depending on the speed, braking force and ambient conditions (such as temperature and relative humidity).
Due to the material properties of the ceramic brake discs*, noises may develop in particular at low driving speeds.
Effect of moisture and salt
In certain conditions, such as in heavy rain, early morning dew, or after washing the car or driving through water, the full braking effect can be delayed by moisture (or in winter by ice) on the discs and brake pads. The brakes should be “dried” by pressing the pedal to restore full braking effect.
When you are driving at higher speeds with the windscreen wipers on, the brake pads are very briefly brought into contact with the brake discs. This automatic process which goes unnoticed by the driver is carried out at regular intervals and is intended to improve braking response in wet conditions.
The effectiveness of the brakes can also be temporarily reduced if the car is driven for some distance without using the brakes when there is a lot of salt on the road in winter. The layer of salt that accumulates on the discs and pads can be removed with a few cautious brake applications.
Due to their surface structure, ceramic brake discs* absorb moisture under such conditions. This can cause a temporary reduction in braking performance in comparison to dry brakes. You can compensate for this by applying greater pressure to the brake.
Corrosion
There may be a tendency for dirt to build up on the brake pads and corrosion to form on the discs if the car is used infrequently, or if you only drive low mileages without using the brakes very much.
If the brakes are not used frequently, or if corrosion has formed on the discs, it is advisable to clean off the pads and discs by braking firmly a few times from a moderately high speed ►.
Faults in the brake system
If the brake pedal travel should ever increase suddenly, this may mean that one of the two brake circuits has failed. Drive immediately to the nearest qualified workshop and have the fault rectified. On the way to the dealer, be prepared to use more pressure on the brake pedal and allow for longer stopping distances.
Low brake fluid level
Malfunctions can occur in the brake system if the brake fluid level is too low. The brake fluid level is monitored electronically.
Brake servo
The brake servo amplifies the pressure you apply to the brake pedal. It only works when the engine is running or the ignition is switched on (plug-in hybrid drive*).
- When applying the brakes to clean off deposits on the pads and discs, select a clear, dry road. Be sure not to inconvenience or endanger other road users; do not risk an accident.
- Never let the car coast with the engine switched off (this can cause accidents).
- On some models, the brake pedal is drawn in automatically when the vehicle initiates a braking manoeuvre.
- Never place objects in the driver s footwell. Such objects could move under the pedals and interfere with their proper function. In the event of sudden braking or a change of direction, you would not be able to use the pedals. This could result in a loss of control and possibly cause an accident.
- Only use floor mats which leave the pedal area free and can be securely fastened in the footwell – risk of accident!
- Do not rest your foot underneath the brake pedal – risk of injury!
CAUTION
- Never let the brakes “drag” by leaving your foot on the pedal when you do not really intend to brake. This overheats the brakes, resulting in longer stopping distances and greater wear.
- Before driving down a long, steep gradient, it is advisable to reduce speed and select a lower gear. In this way you will make use of the engine braking effect and relieve the load on the brakes. If you still have to use the brakes, it is better to brake firmly at intervals than to apply the brakes continuously.
Note
- If the brake servo is out of action, you must apply considerably more pressure to the brake pedal than you normally would.
- If you wish to equip the car with accessories such as a front spoiler or wheel covers, it is important that the flow of air to the front wheels is not obstructed, otherwise the brakes can overheat.