Power brakes function only when theengine is running

Power brakes function only when theengine is running  - Brake system - Starting and driving - Volvo XC90 Owners Manual - Volvo XC90

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:

    How BLIS functions in daylight and darkness
    Daylight BLIS reacts to the shape of surrounding vehicles. The system is designed to help detect motor vehicles such as cars, trucks, buses, motorcycles, etc. Darkness BLIS reacts to the headligh ...

    Re-assembling the remote key
    1. Press the remote key's cover into place. 2. Hold the remote key with the slot for the key blade up. 3. Carefully slide the key blade into its groove. 4. Gently press the key blade in the groov ...

    Design concept
    At the front, the traditional Volvo V-shaped bonnet incorporates a grille with a wide chrome surround and three-dimensional mesh inserts, plus a large Volvo 'iron mark' badge. The front bumper has ...