At peak times the signals will be operated manually to assist the flow of traffic past the roadworks.
The work is being undertaken by Sure and Geomarine. They expect to complete it on Wednesday.
Announcing the closure yesterday, the States said: “As with all works that take place on the inter-harbour route, drivers can expect delays, especially at peak times, and should allow extra time for their journeys through the area and adjacent roads during the period of the works.”
Pictured: A map of where the roadworks will take place between this coming Saturday and Wednesday next week. The green line indicates single file traffic along the section of road concerned – between First Tower Lane and the Red Lion.