2010 Buick LaCrosse Owner's Manual - Page 263

Driving and Operating How the System Works SBZA displays do not come on while the vehicle is approaching or passing other vehicles. At speeds greater than 32 km/h (20 mph), SBZA displays may come on when a vehicle you have passed remains in or drops back into the detection zone. SBZA can be disabled through Vehicle Personalization. See Vehicle Personalization on page 4‑38 for more information. If the SBZA is disabled by the driver, the SBZA mirror displays will not light up during normal driving. 8-43 When the System Does Not Seem To Work Properly Occasional missed alerts can occur under normal circumstances and will increase in wet conditions. The system does not need to be serviced due to an occasional missed alert. The number of missed alerts will increase with increased rainfall or road spray. If the SBZA displays do not light up when the system is on and vehicles are in the blind zone, the system may need service. Take the vehicle to your dealer/retailer. SBZA is designed to ignore stationary objects; however, the system may occasionally light up due to guard rails, signs, trees, shrubs, and other stationary objects. This is normal system operation, the vehicle does not need service. Left Side Mirror Right Side Mirror Display Display When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. While driving forward, the left or right side mirror SBZA display will light up if a vehicle is detected in that blind zone. If you activate a turn signal and a vehicle has been detected on the same side, the SBZA display will flash to give you extra warning not to change lanes.