Stopping Intrusive Government Now Act of 2011 or SIGN Act of 2011 - Prohibits the Secretary of Transportation (DOT) from promulgating, implementing, or enforcing a minimum retroreflectivity level standard for a traffic control device under the jurisdiction of a state or local government.
Directs the Secretary to modify the Manual on Uniform Traffic Control Devices for Streets and Highways, 2009 Edition, to eliminate federal minimum retroreflectivity level standards for traffic control devices and the schedule for their implementation. (Replacement of regulatory, warning, and post-mounted guide [except street name] signs is required by January 22, 2015. Replacement of street name signs and overhead guide signs is required by January 22, 2018.)
Repeals the requirement that the Secretary revise the Manual to include a federal standard for a minimum level of retroreflectivity for pavement markings and signs on all public roads.