Guide to Troubleshooting Photocell Sensors

This security light has a photocell and a motion sensor.
••• Jupiterimages/ Images

Outdoor lighting enhances a home's exterior and acts like a guide to direct visitors down a pathway. Many lighting systems utilize photocell sensors to automatically activate lighting, but the photocell can malfunction at times requiring simple troubleshooting procedures.


A photocell sensor is an electronic component, typically a resistor, that detects levels of light. As the sun sets, the photocell senses the light waning. As a result of less light, the photocell activates the lighting system.


One common problem that affects photocell functioning is incorrect or loose wiring between the photocell and the main circuitry of the lighting system. The wire that connects the photocell to the lighting circuit needs to have a solid, soldered connection. In addition, the system needs to have proper electrical power. Verify that all connections are securely fastened to he power supply.


Over time, photocells can suffer from small cracks within their assembly. These cracks can result in intermittent lighting, or even no light activation at all. Inspect the photocell for any aberrations. If cracked, replacement is the only option.

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