2010 GMC Savana 2500 Cargo Owner's Manual - Page 115

Rear Door Security Locks Security locks are located on the front portion of the 60/40 side swing-out door or the side sliding door. For the 60/40 side swing-out door, move the button to the right for the driver side door or to the left for the passenger side door to engage the security feature. Move the button to the left for the driver side door or to the right for the passenger side door to return the door locks to normal operation. For the side sliding door, move the button up to engage the security feature. Move the button down to return the door locks to normal operation. Side Sliding Door 60/40 Swing-Out Side Door - Driver Side shown, Passenger Side similar 3-11