Security Light Not Coming On
- How urgent
- Low risk
- Who fixes it
- An electrician
What's happening?
PIR (Passive Infrared) security lights detect body heat and movement to trigger illumination. When they stop working, the fault is usually with the PIR sensor, the bulb, the electrical supply, or the settings. Most UK homes have at least one PIR security light above a doorway or driveway.
Book an electrician
What usually causes it?
- PIR sensor has failed or become misaligned
- Bulb has blown (especially halogen floodlights which have a shorter lifespan)
- Sensitivity or range setting turned too low
- Timer set to a very short duration so the light appears not to work
- Spider webs or dirt covering the PIR sensor lens
Is it dangerous?
A non-working security light is not an electrical danger, but it is a security risk. A dark entrance or driveway makes your home more vulnerable to break-ins and increases the risk of trips and falls.
Can I fix it myself?
Start with the obvious: check and replace the bulb. Clean the PIR sensor lens with a damp cloth to remove dirt, cobwebs, and insects. Check the sensitivity and timer dials on the light (usually small adjustable knobs on the unit). Make sure the range setting is not set to minimum and the timer is not set to the shortest duration. Some PIR lights have a manual override: check if it has been switched to the off position.
When should you call an electrician?
Call an electrician if the bulb is fine and the sensor appears clean but the light still does not work, if the light has power but the PIR sensor has failed, or if you want to upgrade to a modern LED security light. If the light is hard-wired (not plug-in), any replacement work should be done by an electrician.
What will the electrician actually do?
- Test the supply to the security light to confirm power is reaching it
- Check the PIR sensor function and replace if faulty
- Replace the entire fitting if it is beyond repair or outdated
- Adjust the sensor angle, sensitivity, and timer for optimal coverage
- Upgrade to a modern LED PIR light for better reliability and lower energy use
Who fixes this
What it usually costs
- Electrical Fault Finding Cost
- Priced on survey
Questions people ask
Why has my security light stopped detecting movement?
How long do PIR security lights last?
Can I replace a security light myself?
Why does my security light only work sometimes?
Sources & References
Before you book, read how to check an electrician is qualified.
What would yours cost?
We'll tell you the price for this, then find a local electrician to do it.
Get my instant quote