Speed cameras on the M25 have not been operating since their installation in 2009, but all that is due to end in Surrey this summer.
The cameras, already installed on the motorway and with warning signs aplenty, sit dormant behind overhead signs that tell drivers to reduce their speed to 60, 50 or 40mph during busy periods.
But the cameras have not flashed once since they were installed and many motorists have happily, and dangerously, exceeded the speed limit without comeback on almost the entire London orbital.
The cameras currently only work in between junctions two and three of the motorway.
But further flashes could be coming soon, with cameras between junction 10 at Cobham and the M40 due to be working by the summer.
A Highways Agency spokesman said: “Sections of the M25 where mandatory speed limits are displayed in red rings have continued to work effectively to reduce congestion and smooth traffic flow and have operated well without fixed camera enforcement.
“We are working with Surrey Police, who are taking over responsibility between junctions 10 and 16, to resume enforcement.
“The speed limits are enforceable by the police and the cameras will be operational by summer 2014.”