Speed cameras targeting a hotspot for dangerous driving are still not active - six months after being installed.
The average-speed cameras were placed on parts of the so-called "Evo Triangle" in north Wales - a stretch of road spanning Conwy and Denbighshire.
Four people have died since 2012 on the roads, named after the motoring magazine Evo.
The partnership responsible for the scheme said it was "waiting for the final cameras to be commissioned".
The roads connect Llyn Brenig, Pentrefoelas and Cerrigydrudion, with Denbighshire and Conwy councils receiving a £500,000 Welsh government grant to install cameras on the A453 routes.
A statement on behalf of the two councils, North Wales Police, and GoSafe - the Welsh road casualty reduction partnership - said: "Enforcement is being supported by mobile units from North Wales Police Roads Policing Unit and GoSafe in order to ensure compliance with the speed limit on this route.
"We have already had positive feedback from communities that have seen a reduction in speeds."
Go Safe said funding for a second phase of cameras, on the B4501, has also been secured and work will be carried out in early 2020.
A Welsh government official added: "The A543 Average Speed Camera scheme is a multi-agency initiative to address the number of collisions on this road.
"Conwy and Denbighshire county councils are still in the commissioning phase with enforcement being supported by North Wales Police Roads Policing Unit and GoSafe in order to ensure compliance with the speed limit on this route."