2008 Subaru Impreza Owner's Manual - Page 260

7-38 NOTE Starting and operating . Slight twitching of the brake pedal may be felt when the Vehicle Dynamics Control system operates; a small degree of vehicle or steering wheel shaking may also be noticed in this situation. These are normal characteristics of Vehicle Dynamics Control operation and are no cause for alarm. . When driving off immediately after starting the engine, a short-lived operation noise may be noticed coming from the engine compartment. This noise is generated as a result of a check being performed on the Vehicle Dynamics Control system and is normal. . Depending on the timing of activation of the brakes, the brake pedal may seem to jolt when you drive off after starting the engine. This is a consequence of the Vehicle Dynamics Control operational check and is normal. . In the circumstances listed in the following, the vehicle may be more unstable than it feels to the driver. The Vehicle Dynamics Control System may therefore operate. Such operation does not indicate a system fault. - 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. . Even if the vehicle is equipped with a Vehicle Dynamics Control system, it is important that winter tires be used when driving on snow-covered or icy roads. (All four wheels should be fitted with tires of the same size and brand.) Furthermore, if snow chains are to be used, they should be fitted on the front wheels. When a vehicle is fitted with snow chains, however, the effectiveness of the Vehicle Dynamics Control system is reduced and this should be taken into account when driving the vehicle in such a condition. . It is always important to reduce speed when approaching a corner, even if the vehicle is equipped with Vehicle Dynamics Control. . All four wheels should be fitted with tires of the same size, type, and brand; furthermore, the amount of wear should be the same for all four tires. If these precautions are not observed and non-matching tires are used, it is quite possible that the Vehicle Dynamics Control system will be unable to operate correctly as intended. . Always turn off the engine before replacing a tire as failure to do so may render the Vehicle Dynamics Control system unable to operate correctly. & Vehicle Dynamics Control system monitor ! Vehicle Dynamics Control operation indicator light Turbo models