Essential work started this week on the traffic signals at the junction of Braunton Road, Fairview, Rolle Street and Pottington Road in Barnstaple.
The Devon County Council scheme is expected to be completed on Friday, November 27.
Traffic signals, poles and electrics at the end of their serviceable life will be replaced.
Temporary traffic signals will be in place while this work is carried out and for its duration.
The operation of temporary signals will be the same as permanent signals during peak and daytime hours.