Volvo XC90 Owner's Manual page 396

STARTING AND DRIVING
|| Ignition mode I – Turn the start knob clock-
•
wise and release it. The control will automati-
cally return to the original position.
Ignition mode II – Turn the start knob
•
clockwise and hold it there for
approx. 5 seconds. Release the knob, which
will automatically return to its original posi-
tion.
Back to ignition mode 0 – To return to
•
ignition mode 0 from modes I and II, turn the
start knob clockwise and release it. The con-
trol will automatically return to the original
position.
Related information
• Starting the vehicle (p. 390)
• Switching off the vehicle (p. 392)
• Ignition modes (p. 392)
• Adjusting the steering wheel (p. 203)
• Jump starting using another battery (p. 432)
394
Brake functions
The vehicle's brakes are used to reduce speed
or prevent the vehicle from rolling.
In addition to the wheel brakes and parking
brakes, the vehicle is also equipped with a num-
ber of automatic brake assist functions. These
systems help the driver by e.g. keeping the vehi-
cle stationary when the brake pedal is not
depressed (e.g. at a traffic light or intersection),
when starting up a hill or when driving down a hill.
Depending on how the vehicle is equipped, the
following brake assist functions may be included:
• Auto-hold brake function at a standstill (Auto
Hold)
• Hill Start Assist (Hill Start Assist)
• Braking assist after a collision
• City Safety
•
Hill Descent Control (Hill Descent Control)*
Related information
• Brakes (p. 394)
• Parking brake (p. 397)
• Auto-hold brakes (p. 401)
• Braking assist after a collision (p. 402)
• Hill Start Assist (p. 402)
• City Safety™ (p. 321)
•
Hill Descent Control* (p. 422)
Brakes
The brake pedal is used to apply the vehicle's
regular brakes, which are part of the brake sys-
tem.
The vehicle is equipped with two brake circuits. If
one brake circuit is damaged, the brake pedal will
go down further when depressed. More pressure
will then be required from the driver for normal
braking effect.
The driver's pressure on the brake pedal is
enhanced by a power braking function.
WARNING
Power braking only functions if the engine is
running.
If the brake pedal is used when the engine is
turned off, the pedal will feel stiffer than usual
and greater pressure must be applied to brake
the vehicle.
In very hilly areas or when driving with a heavy
load, engine braking in manual gear should be
used to augment the brakes. Engine braking is
most effective if the same gear is used both
uphill and downhill. Use the Off Road* drive mode
to increase the engine braking effect when driv-
ing on steep downgrades at low speeds.
* Option/accessory.