2008 Volvo V70 Owner's Manual - Page 143

A pulsating sound will be audible when the system is actively operating and is normal. Traction control (TC) This function is designed to help reduce wheel spin by transferring power from a drive wheel that begins to lose traction to the wheel on the opposite side of the vehicle (on the same axle). TC is most active at low speeds. This is one of DSTC's permanent functions and cannot be switched off. Active Yaw Control (AYC) This function helps maintain directional stability, for example when cornering, by braking one or more of the wheels if the vehicle shows a tendency to skid or slide laterally. This is one of DSTC's permanent functions and cannot be switched off. Spin control (SC) The spin control function is designed to help prevent the drive wheels from spinning while the vehicle is accelerating. Under certain circumstances, such as when driving with snow chains, or driving in deep snow or loose sand, it may be advisable to temporarily switch off this function for maximum tractive force. WARNING The car's handling and stability characteristics will be altered if the spin control function has been disabled. Operation Temporarily switching off Spin control 1. Turn the thumbwheel until the DSTC menu is shown. 2. Hold down the RESET button to toggle between DSTC SPIN CONTROL ON or OFF. Messages in the information display DSTC Temporarily OFF - system function has been temporarily reduced due to high brake disc temperature. The function is activated automatically when the brakes have cooled. DSTC Service required - the system has been disabled due to a fault. If this occurs: 154 04 Comfort and driving pleasure Stability system