We have a light connected to a motion detector in our backyard. It detects motion and turns on the light for 2-3 seconds, then the light turns off again, and won't detect further motion.
A single switch inside the house powers both the motion detector and a patio light. The patio light turns on and off with no issues.
Interestingly, if I leave the patio light on for several hours, the motion detector will stay on longer. It will continue detecting motion & stay on for several minutes.
Do you have any advice for troubleshooting why it won't stay on? It is about 20 feet off the ground, so anything we could do to figure this out without needing to rent a giant ladder would be helpful. I tried to get close enough to determine the brand but could not. Generic white security lighting.