How to detect and replace non-working LED bulbs?

When LED lights do not work, there are mainly two reasons: one is an issue with the light source, and the other is a problem with the power supply. Currently, LED lights are composed of LED beads. First, turn off the power at home, remove the lampshade, and use a multimeter to check if the LED light source is faulty (the beads are usually connected in series). If it is, check the style of the light source and purchase a matching one on Taobao. There is a store called Qianhan that has a complete range of accessories. When buying, pay attention to the voltage range of the light source and ensure you purchase one with the same voltage.

If the multimeter indicates that the light source is fine, then check if there is an issue with the power supply. Generally, LED ceiling lights use an external power supply, so you can simply buy a replacement power supply. Some LED manufacturers use poor-quality power supplies, which are the most likely components to fail.

Method 1:

Before turning on the LED light, measure the voltage of the power supply and the current flowing through the LED.

Then, disassemble the light and check all key components one by one: the driver or power supply, and the LED beads. Replace all faulty beads.

Identify the cause of the LED bead failure. If it’s due to overcurrent, immediately reduce the driving current. Check if the driver is faulty, and determine the cause. Repair if possible; replace if not.
If the LED power supply is damaged, buy a power supply with the same voltage and current parameters for replacement.
If many LED lights are damaged, and the faulty LED chips are concentrated in the same area, you can cut out the damaged section and re-solder it.
If you have some basic electronic knowledge, you can buy the same model of LED light, bring a soldering iron, and re-solder it. However, keep in mind that each LED strip contains many LED chip components, and losing one or two will not significantly affect brightness.

Method 2:

If the LED power supply is damaged, buy a power supply with the same voltage and current parameters for replacement.

If many LED lights are damaged, and the faulty LED chips are concentrated in the same area, you can cut out the damaged section and re-solder it.

If you have some basic electronic knowledge, you can buy the same model of LED light, bring a soldering iron, and re-solder it. However, keep in mind that each LED strip contains many LED chip components, and losing one or two will not significantly affect brightness.