Ikea LED1836G9 - Interesting failure mode

I’ve had an Ikea Trådfri LED1836G9 fail, and I wondered what would be wrong with it. It just dropped from my Zigbee network, and re-applying power did not change anything. Would it be the LED’s? Just a simple fuse? Let’s dive in.

To take these apart, just apply some gorilla-strength and pull apart the milk white dome from the body of the housing. You’re then greeted by a removable LED-board, held in place with some screws. Nice construction. All modular.

The power supply can be removed as well, without damaging anything. It’s amazing that something that is considered “disposable”, has such a nice, repairable construction. Well done Ikea.

However, the power supply board immediately gave away its secrets:

This capacitor failed spectacularly. This is a capacitor that is placed across the mains input, behind a fusible resistor. This capacitor is installed for differential-mode EMI compatibility. It is designed to fail in a short. However, it shouldn’t have failed here. Mains power in this area is quite clean. There is however something that bothers me.

Such capacitors, across mains, must have a correct X-rating. This one seemingly doesn’t. So I don’t know if this is a case of “the overseas manufacturer slipping in a couple of batches of cheaper caps for profit” - or if it’s just an honest mistake.

As you can see from the above picture, there’s no clear indication that this is a proper X-rated capacitor.

After searching around other teardowns of this product, I found one YouTuber who has a good shot of the same bulb, but I noticed something very striking:

Well well - it seems that there is a correct, X-rated capacitor installed. So again: was mine a slip of Quality Control? Or an early batch where this wasn’t deemed an issue? I’m pretty sure mine is an older bulb.

Anyway, it was easily fixed with a correctly specced 150nF X-rated capacitor and a new zero-ohm fusible resistor.

Happy repairing! - 73 de ON8AD