Subaru WRX & WRX STI Manuals 2018 WRX & WRX STI Owner’s Manual | Page 390

7-38 Starting and operating/Vehicle Dynamics Control system trol system is reduced and this should be taken into ac- count when driving the vehi- cle in such a condition. . If you use non-matching tires, the Vehicle Dynamics Control sys- tem may not operate correctly. . The Vehicle Dynamics Control system helps prevent unstable vehicle motion such as skidding using control of the brakes and engine power. Do not turn off the Vehicle Dynamics Control sys- tem unless it is absolutely ne- cessary. If you must turn off the Vehicle Dynamics Control sys- tem, drive very carefully accord- ing to the road surface condition. . Traction Control Function The traction control function is designed to prevent spinning of the driving wheels on slippery road surfaces, thereby helping to maintain traction and directional control. Activation of this function is shown by flashing the Vehicle Dynamics Control operation indicator light. . Skid Suppression Function The skid suppression function is designed to help maintain directional stability by suppressing the wheels’ tendency to slide sideways during steering operations. Acti- vation of this function is shown by flashing of the Vehicle Dynamics Control operation indicator light. In the event of wheelspin and/or skidding on a slippery road surface and/or during cornering and/or an evasive maneuver, the Vehicle Dynamics Control system adjusts the engine’s output and the wheels’ respective braking forces to help maintain traction and directional control. Vehicle Dynamics Control operation indi- cator light NOTE . The Vehicle Dynamics Control sys- tem may be considered normal when the following conditions occur. – Slight twitching of the brake pedal is felt. – The vehicle or steering wheel shakes to a small degree. – An operating sound from the engine compartment is heard briefly when starting the engine and when driving off after starting the engine. – The brake pedal seems to jolt when driving off after starting the engine. . In the circumstances shown in the following list, the vehicle may be less stable than it feels to the driver. The Vehicle Dynamics Control System may therefore operate. Such operation does not indicate a system malfunction. – on gravel-covered or rutted roads – on unfinished roads – when the vehicle is fitted with snow tires or winter tires . Activation of the Vehicle Dynamics Control system will cause operation of the steering wheel to feel slightly different compared to that for normal conditions.