Emergency Braking Function; Removing And Installing City Emergency Braking System - Volkswagen up! 2012 Workshop Manual

up! 2012 ➤
Electrical system - Edition 03.2017
9

Emergency braking function

⇒ "9.1 Removing and installing City Emergency Braking System",
page 120
9.1 Removing and installing City Emergen‐
cy Braking System
General description ⇒ page 120
Removing ⇒ page 121
Installing ⇒ page 121
General description
The emergency braking function detects the traffic situation by
means of the emergency braking function sensor unit - J939- at‐
tached to the interior mirror up to a distance of around 10 metres
in front of the vehicle in a speed range of approximately 5 km/h
to 30 km/h.
If the system detects a possible collision with a vehicle driving in
front, the vehicle is prepared for possible emergency braking. If
the driver does not react to the threat of a collision, the system
can brake the vehicle automatically in order to reduce the speed
for a possible collision. If the emergency braking function deter‐
mines that the driver does not brake sufficiently when faced with
the threat of a collision, the system can increase the braking force
in order to reduce the speed for a possible collision.
In the following situations, it is possible that the emergency brak‐
ing function will not react:
♦ In tight curves
♦ When accelerator pedal is fully depressed
♦ If emergency braking function has been switched off or is faulty
♦ If the laser sensor is dirty, is covered or has overheated
♦ During a snowfall, in heavy rain or in dense fog
♦ If vehicle is offset in relation to other vehicles
♦ When other vehicles cut across the driving direction
♦ When there are oncoming vehicles in the same lane
♦ If vehicles are dirty with a low degree of reflection
♦ When there is a lot of dust in the air
Note
When the emergency braking function triggers a braking proc‐
♦
ess, the pedal travel of the brake pedal decreases. As a result,
the brake pedal feels "harder".
During automatic braking carried out by the emergency brak‐
♦
ing function, it is possible that unusual noises will occur. These
are normal and are caused by the brake system.
Automatic braking triggered by the emergency braking func‐
♦
tion can be cancelled by depressing the clutch pedal or the
accelerator pedal, or by turning the steering wheel.
The sensor unit for the emergency braking function - J939- is lo‐
cated under a cover next to the interior mirror.
120
Rep. gr.94 - Lights, bulbs, switches - exterior