If equipped, the SBZA system is a lane-changing aid that assists drivers with avoiding crashes that occur with moving vehicles in the side blind zone (or spot) areas.
When the vehicle is in a forward gear, the left or right side mirror display will light up if a moving vehicle is detected in that blind zone. If the turn signal is activated and a vehicle is also detected on the same side, the display will flash as an extra warning not to change lanes. Since this system is part of the Lane Change Alert (LCA) system, read the entire LCA section before using this feature.
Forward Automatic
Braking (FAB)
Lane Change Alert (LCA)#PIC5904: OnStar Account Issues Causing No Connect Concern - (Aug 20, 2013)
Subject:OnStar Account Issues Causing No Connect ConcernModels: 2002-2014 GM Passenger Cars and Trucks The following diagnosis might be helpful if the vehicle exhibits the symptom(s) describedin this PI.Condition/ConcernA customer may report they are not able to connect to OnStar on blue button ...