2015 Buick LaCrosse Owner Manual - Page 228

Driving and Operating range of selectable gaps may not be appropriate for all drivers and driving conditions. Changing the gap setting automatically changes the alert timing sensitivity (Far, Medium, or Near) for the Forward Collision Alert (FCA) feature. See Forward Collision Alert (FCA) System on page 9-50. Alerting the Driver Alert Seat will pulse five times. See "Collision/Detection Systems" under Vehicle Personalization on page 5-45. See Defensive Driving on page 9-3. Approaching and Following a Vehicle 9-43 selected follow gap. The vehicle speed increases or decreases to follow the vehicle in front of you, but will not exceed the set speed. It may apply limited braking, if necessary. When braking is active, the brake lights will come on. The automatic braking may feel or sound different than if the brakes were applied manually. This is normal. Stationary or Very Slow-Moving Objects { Warning The vehicle ahead symbol is in the instrument cluster and HUD display. The vehicle ahead symbol only displays when a vehicle is detected in your vehicle's path moving in the same direction. If this symbol is not displaying, ACC will not respond to or brake to vehicles ahead. ACC automatically slows the vehicle down and adjusts vehicle speed to follow the vehicle in front at the Adaptive Cruise Control (ACC) may not detect and react to stopped or slow-moving vehicles ahead of you. For example, the system may not brake for a vehicle it has never detected moving. This can occur in stop-and-go traffic or when a vehicle suddenly appears due to a vehicle ahead changing lanes. Your vehicle may not stop and (Continued) If ACC is engaged, driver action may be required when ACC cannot apply sufficient braking because of approaching a vehicle too rapidly. When this condition occurs, the collision alert symbol on the HUD will flash on the windshield. Either eight beeps will sound from the front, or both sides of the Safety