I just purchased a new Defiant model# DFI 5852 BK security light to replace an older one. After installation..the motion sensor flashes red but lights do not come on..Tried adjusting sensitivity, & Test modes, No change..
The sensor flashing red is telling you that the sensor sees you. It's not turning on because only a fool would turn the lights on in broad daylight. Yes, it knows it is broad daylight because it also has a light sensor.
If it is in fact night, then you have an unusual amount of artificial lighting in the area, and that is fooling the sensor. However, most sensors have a learning feature if you leave the system energized 24x7, and after a couple day/night cycles it will learn what normal light levels are here.
If you cut power to the sensor, you will wipe its memory and it will have to start the learning process all over again. So don't do that.