CCTV no signal: camera not showing on the DVR

Look at the recorder's own screen, not just your phone, and note which cameras are missing:

How a camera gets its picture and its power depends on the system:

• A DVR system uses analogue HD cameras on coaxial cable, usually with a separate power supply for the cameras.
• An NVR system uses IP cameras on network cable, and the cameras are usually powered over the same cable, often through a network switch.

The recorder's label, or the cable at the back of a camera, tells you which you have. Our CCTV page explains both.

The fault is somewhere between that camera and its input on the recorder:

• No power at the camera. A camera that has lost power goes dark. At night, many cameras show a faint red glow from their infrared lights when they're powered, which is a useful clue from the ground.
• A connector. Outdoor connections let water in over time, and corroded or loose ones lose the picture, often after rain.
• The cable. Cut by a garden service, chewed by a rodent, crushed by building work, or damaged by a lightning surge.
• The camera itself, after years in the sun and rain, or a surge.

A technician finds which by testing the camera on a known-good cable and input, and the cable with a known-good camera. That quickly separates a connector job from a new camera.

When two or more cameras vanish together, look at what they share. On a DVR system, that's usually the camera power supply: one supply often feeds several cameras, and when it fails, they all go. On an NVR system, it's often the network switch that powers them. Both are common casualties of a power surge. A camera power supply that's warm and silent, or a switch with no lights, is the likely culprit.

• Is the recorder on? Look for its lights and listen for its fan.
• Is it the monitor? If the phone app still shows the cameras, the cameras and recorder are fine and the fault is the monitor or its cable.
• After a power cut or storm, a surge may have damaged the recorder, the camera power supply or both.

Restarting the recorder from its menu, or switching it off and on at its plug, is a safe first step. If it doesn't come back with its cameras, leave it for us.

If the recorder's own screen shows every camera, nothing is wrong with the cameras. The phone app reaches the recorder through your internet connection, so a new router, changed Wi-Fi details, an internet outage or an app update can break the link. Check the internet is working, and that the recorder is still plugged into the router. Reconnecting the recorder to a new router is a quick job for us.

At night, most cameras switch to black-and-white and light the scene with infrared. If the picture goes black or white-out at night only, the infrared lights may have failed, or a spider web or dust on the lens is reflecting them back into the camera. Cleaning a lens is only worth doing if you can reach the camera safely from the ground; anything on a ladder is a job for us.

The return of the power, or a nearby lightning strike, can take out power supplies, cameras, switches and recorders, often several at once. A UPS that runs the recorder, the camera power supply and the router helps the system ride out load shedding and softens the surge when the power returns. Our CCTV page explains how we size one.

Safe checks stop at the recorder, the monitor, the router and the plugs you can reach from the ground. Call us for anything on a ladder, inside a camera or a power supply, or on the mains, and whenever cameras stay dark after a restart. We repair Hikvision, HiLook and Dahua systems, whoever installed them. All our spare parts are genuine, and every repair comes with our six-month guarantee on our repairs.

On the job card, give the recorder's make, which cameras are missing, and whether it happened after rain, a storm or a power cut; a photo of the recorder's screen helps. Same-day repairs are offered when the day allows. No call-out fee when we do the work. If no work is done, a R650 call-out fee applies.