Volvo 2004 XC90 Owner's Manual - Brake System (Contd)
2004 VOLVO XC90
Driving in rain and slush or passing through an automatic car wash can cause water to collect on the
brake discs and pads. This will cause a delay in braking effect when the pedal is depressed. To avoid
such a delay when the brakes are needed, depress the pedal occasionally when driving through rain,
slush, etc. This will remove the water from the brakes. Check that brake application feels normal. This
should also be done after washing or starting in very damp or cold weather.
Severe strain on the brake system
The brakes will be subject to severe strain when driving in mountains or hilly areas, or when towing a
trailer. Vehicle speed is usually slower, which means that the cooling of the brakes is less efficient than
when driving on level roads. To reduce the strain on the brakes, shift into a lower gear and let the engine
help with the braking. Do not forget that if you are towing a trailer, the brakes will be subjected to a
greater than normal load.
pg. 94 Starting and driving
Brake system (contd)
Anti-lock brakes (ABS)
If the warning lamp lights up there is a malfunction of the ABS system (the standard braking system will
however function) and the vehicle should be driven cautiously to a Volvo retailer for inspection. The
Anti-lock Braking System (ABS) helps to improve vehicle control (stopping and steering) during severe
braking conditions by limiting brake lockup. When the system "senses" impending lockup, braking
pressure is automatically modulated in order to help prevent lockup, which could lead to a skid.
This system performs a self-diagnostic test when the engine is started and when the vehicle first
reaches a speed of approximately 12 mph (20 km/h). The brake pedal will pulsate several times and a
sound may be audible from the ABS control module. This is normal.
To obtain optimal effect from the ABS system, constant pressure should be kept on the brake pedal,
keep constant pressure on the brake pedal. Do not pump the brake pedal.
The switching of the ABS modulator will be audible and the brake pedal will pulsate during braking.
Please be aware that ABS does not increase the absolute braking potential of the vehicle. While control
will be enhanced, ABS will not shorten stopping distances on slippery surfaces.
ABS with EBD (Electronic Brake Force Distribution)
EBD is an integrated part of the ABS system. EBD regulates the hydraulic pressure to the rear brakes to
help provide optimal braking capacity. The brake pedal will pulsate during braking, which is normal.
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