LED light problem

[ingrid75]

I have a two bulb light fixture in my galley. Both " bulbs" are nine element LED clusters. Each bulb is controlled by it's own switch. Positive and negative wires are common until the positive wires split off to the separate switches. About a month ago, one of the bulbs dimmed and started flickering. It turned out that only three of the nine elements were flickering, the other six weren't working at all. I replaced the "bulb" but there was no change. Still 3 flickering elements and 6 dead ones. I replaced the switch. No change. I replaced the socket,No change. I renewed the wires from the common positive and negative wires. No change. The other "bulb" that feeds off of the common wires works fine. As my wife says, we can live without the extra light, but this is very puzzling. What could the problem be?

[dlymn]

LEDs are very voltage sensitive. A 12 v LED will behave erratically if the voltage drops to 11.99v. Even the slightest voltage variation will cause them to flicker. If your fridge is running, the lights will misbehave. and voltage drop will cause them to act up. Even the variation from a 12v sound system will affect them. Check your supply voltage under load. Swap the LEDs and see what happens. Heavier wires might help but somehow, you need to provide a stable 12+ volts. You might need to have a separate battery that drives only the lights. If you are only charging from an alternator, that might not charge the batteries to a high enough level of charge.

[meridian28]

have you placed any other electronic devices near by?

[Stu Jackson]

Who made the fixture? And the lamps. Sometimes folks will know about manufacturers' defects and chime in. Why not share that info?

[Seeking Solace]

Originally Posted by ingrid75

I have a two bulb light fixture in my galley. Both " bulbs" are nine element LED clusters. Each bulb is controlled by it's own switch. Positive and negative wires are common until the positive wires split off to the separate switches. About a month ago, one of the bulbs dimmed and started flickering. It turned out that only three of the nine elements were flickering, the other six weren't working at all. I replaced the "bulb" but there was no change. Still 3 flickering elements and 6 dead ones. I replaced the switch. No change. I replaced the socket,No change. I renewed the wires from the common positive and negative wires. No change. The other "bulb" that feeds off of the common wires works fine. As my wife says, we can live without the extra light, but this is very puzzling. What could the problem be?

#1 cause would be a low voltage. It could also be a poor ground not allowing current to flow through the diode. If you're measuring good voltage at the fixture and it isn't low with your multimeter, consider checking your ground connections and cleaning all terminals. A small voltage regulator board with a capacitor bank will help stabilize the power flickering at LED fixtures, but is really overkill for most applications. The current consumption for an LED array is pretty small. Voltage regulator chip packages and support components could be easily mounted behind the fixture and take up only a couple inches of space.

If you feel that it's not a voltage issue or a connector issue you might want to try a different brand of LED array. There are huge differences in quality control from manufacturer to manufacturer. I've had those screw in arrays that were very poorly soldered. They were also oriented in a triangle instead of forward facing. The boards were terribly constructed and had a lot of bridged connections and defects that kept otherwise good diodes from lighting. It was tedious to fix, but after some time with the soldering iron I got them working right.

Since yours was working and now is not, likely it is a voltage or poor connection issue rather than quality of construction.

Remember a diode only works when the energy is flowing in the right direction. If you wire them backwards they will try to block the flow of energy until you reach the PIV (Peak Inverse Voltage) and they make a nice pop when the smoke comes out.