LED lights flickering

Flickering is the most common complaint with LED strip lights. In almost every case it comes down to one of three things: an incompatible dimmer switch, a loose connection, or a power supply that is struggling under load.

Most likely causes:

• Dimmer switch not rated for LED — most older trailing-edge dimmers are designed for halogen bulbs and will cause LED strips to flicker or buzz
• Loose wire connection at the driver output or at a strip connector
• Power supply undersized for the total wattage of the run
• Voltage drop on a long run — the strip draws more current at the start and dims or flickers at the far end

How to fix it:

• Replace any trailing-edge dimmer with a leading-edge LED-compatible dimmer — check the dimmer minimum load matches your strip wattage
• Check and firmly reseat every connector along the run — clip connectors can work loose over time
• Calculate the total wattage and ensure your driver output is no more than 80% loaded
• For runs over 5 metres, use a driver at each end or mid-feed rather than running from one end only

LED lights not turning on

If your LED lights have power but are not illuminating at all, the fault is almost always at the driver, the connection between driver and strip, or the strip itself.

• Check the driver — is the power indicator light on? If not, check the mains connection and fuse
• Test the output voltage at the driver terminals with a multimeter — it should read 24V for all Lumily strips
• Check the polarity of the connection — LED strips are polarity sensitive. Positive to positive, negative to negative
• Check for a blown fuse in the driver
• Try connecting a short test strip directly to the driver to isolate whether the fault is in the strip or the wiring

LED lights dimmer at one end

If your strip lights up brightly at the driver end but fades noticeably towards the far end, this is voltage drop. As electrical current travels along a conductor it meets resistance — over a long run, this causes the voltage at the far end to be lower than at the driver end.

How to fix it:

• Feed from both ends — run a cable from the driver to both the start and end of the strip, halving the effective run length
• Mid-feed — connect the driver at the centre of the run rather than one end
• Use a higher-gauge wire between driver and strip to reduce resistance
• Split long runs across two drivers rather than powering from one

LED remote not working

• Check the remote battery — try a fresh CR2032 or AAA battery
• Make sure the controller receiver is connected to power
• Check there is no obstruction between the remote and the receiver — IR remotes need line-of-sight
• If using an RF remote, the controller may need re-pairing — hold the pair button for 5 seconds, then press any button on the remote
• Check the controller receiver is compatible with your strip type — RGB controllers will not work with single-colour or tunable white strips

LED lights showing wrong colours

• Check all four pins at every RGB connector — a single loose pin will cause one colour channel to drop out
• Test whether the fault follows the controller or the strip — connect a different strip to the same controller to isolate the fault
• Ensure the controller channel output matches the strip wiring order — some RGB strips are wired RGB, others GRB. Check the label on the strip