False alarms with motion detectors can be frustrating, but there are a few steps you can take to troubleshoot this issue with your DSC LC-100-PI. Firstly, ensure that the detector is installed at the correct height and angle according to the manufacturer’s instructions. Adjusting the sensitivity settings can also help, as the pet immunity feature may need to be calibrated properly for your specific pet’s size and movement patterns. Additionally, check for any potential sources of interference such as direct sunlight, moving curtains, or heat vents, which could trigger false alarms. Finally, make sure the detector is clean and free of any obstructions that could cause erratic behavior. Following these steps should help minimize false alarms and ensure the reliable operation of your motion detector.