See also:

Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-521-7300, or write: Buick Customer Assistance Center P.O. Box 33136 ...

Unlock Feedback (Lights)
When on, the exterior lamps will flash when unlocking the vehicle with the RKE transmitter. Press SELECT when Unlock Feedback (Lights) is highlighted. Turn the Menu knob to select On or Off. ...

Underbody Maintenance
Use plain water to flush dirt and debris from the vehicle's underbody. Your dealer or an underbody car washing system can do this. If not removed, rust and corrosion can develop. ...