2008 Volvo S40 Owner's Manual - Page 135

speed-, traction- , temperature-, and treadwear rating. Never drive on mixed tires, except for brief periods when the temporary spare tire is in use. Always use properly inflated tires of correct dimensions. Tire size and inflation pressures are shown on a placard located on the driver's side B-pillar (the structural member at the side of the vehicle, at the rear of the driver's door opening). See also the tire inflation pressure tables beginning on page 172. Temporary Spare The temporary spare tire is for temporary, low-speed, short-distance use only. Replace it with a full-sized tire as soon as possible. Do not drive on the temporary spare at speeds above 50 m.p.h. (80 km/h). Never install snow chains on a temporary spare. 147 06 Starting and driving Brake system Brake circuit malfunction The brake system is a hydraulic system consisting of two separate brake circuits. If a problem should occur in one of these circuits, it is still possible to stop the vehicle with the other brake circuit. If the brake pedal must be depressed farther than normal and requires greater foot pressure, the stopping distance will be longer. A warning light in the instrument panel will light up to warn the driver that a fault has occurred. If this light comes on while driving or braking, stop immediately and check the brake fluid level in the reservoir. NOTE Press the brake pedal hard and maintain pressure on the pedal - do not pump the brakes. 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 trained and qualified Volvo service technician 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