Power Brakes Function Only When The Engine Is Running; Water On Brake Discs And Brake Pads Affects Braking; Severe Strain On The Brake System; Anti-Lock Brakes (Abs) - Volvo S40 2005 Owner's Manual

2005 Volvo S40
WARNING!
If the fluid level is below the MIN mark in the reservoir or if a brake system message is shown in the
information display: DO NOT DRIVE. Have the vehicle towed to a Volvo retailer and have the brake
system inspected.

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, the brake pedal must be pressed approximately five times harder
than usual to make up 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.

Water on brake discs and brake pads affects braking

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.

Anti-lock brakes (ABS)

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 that could lead to a skid.
The system performs a self-diagnostic test when the engine is started and when the vehicle first
reaches a speed of approximately 12 m.p.h. (20 km/h). The brake pedal will pulsate several times and
a sound may be audible from the ABS control module. This is normal.
pg. 112 Brake system
NOTE: To obtain optimal effect from the ABS system:
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