Red light cameras at San Jose Boulevard and Claire Lane, both northbound and southbound approaches, are set to be in test phase throughout the weekend.
A 30-day grace period is expected to begin Monday, the Jacksonville Sheriff's Office said.
As cameras are placed, calibrated and tested, motorists may notice some white flashes. That is the testing mode. No notices are issued during that time.
For more information on Jacksonville's Red Light Enforcement Program, click on the Respect the Red logo on the right side of the Sheriff's Office's homepage under Traffic News.