Some time ago I bought a Philips SHB3060 bluetooth headset from Technopolis (a chain of consumer electronics stores in Bulgaria). After just a couple of weeks of usage it broke with the symptom of not turning ON at all. It was exchanged under warranty, but at the price of an awful customer experience rivaling that during the communist times. It failed yet again, in exactly the same manner. I decided to take the matters in my own hands, even if there’s more than a year of warranty left.
The first step of disassembly is to remove the ear cushion by carefully pulling it aside:
After that you’ll reach a small Philips screw:
Next the plastic cover needs to be popped off. It’s held by a few clips and a little help from a flat headed screw driver can be useful to avoid breaking them:
Remove the second Philips screw and you can finally take the PCB out:
It was immediately obvious what is the problem:
The travel of the plastic button on the enclosure is not limited in any way. Because of that the small microswitch on the PCB has to endure all of the force, while being held in place only by two tiny solder joints. This has caused one of the PCB traces to lift off and break.
The reaction to the power button is delayed by a couple of seconds, which is a good idea to avoid unwanted presses while in a bag, etc. Unfortunately there is no immediate feedback that the button is actually being pressed (like by blinking the LED near it or something), so sometimes the user tends to exert a little extra force just to be sure, which makes this failure mode even more likely.
I fixed the broken PCB trace with a piece of thin copper wire. The trace is tiny and even under a magnifying glass it was not so easy to work on it (or I’m getting old and my eyesight not as good as it used to be 🙂 ). The headphones came back to life!
To make sure my repair has at least a fighting chance of lasting longer I superglued the whole underside of the microswitch to the PCB. I also hotglued two little pieces of plastic with the right thickness to limit the travel of the plastic button on the enclosure. This way if additional force is exerted on the button it will be taken up by the edge of the PCB (which is pretty strong) and not by the microswitch.
How long will my repair last? Only time will tell, but I’m pretty optimistic it will last longer than replacing the headset under warranty a second time. Bonus points for not having to deal with the grumpy auntie at the local Technopolis store.
