Power brakes function only when the engine is running

The power brakes utilize vacuum pressure which is only created when the engine is running. Never let the vehicle roll to a stop with the engine switched off.
If the power brakes are not working, considerably higher pressure will be required on the brake pedal to compensate for the lack of power assistance. This can happen for example when towing your vehicle or if the engine is switched off when the vehicle is rolling. The brake pedal feels harder than usual.
See also:
Operation
Press to operate the air quality sensor (normal
setting).
or:
Select one of the following three functions by
pressing 1, 2 or 3 times.
1. The AUT LED lights. The air quality sensor
is now acti ...
Function
• HDC can be switched on and off with the
button in the center console. An indicator
light in the button illuminates when HDC is
activated.
• The indicator light in the
instrument
panel ...
Overview
With dynamic design, high quality and class-leading safety, the Volvo S40
saloon is a true Volvo and one that asserts a unique identity in the growing
premium compact class.
Boasting a four-door ...
