Once upon a time, there was a happy owner of an HTC One (M7) Dual sim smartphone, right until the moment he started experiencing problems with its power button, rendering the whole phone unusable. Being out of warranty period, he decided to just take it to a repair shop to get it fixed. To his very surprise, every place he went to turned him down, with reasons ranging from ‘impossible to get a replacement button’ to just ‘not possible, at all’. So in the end he just shelved it and got himself a new one.
This would probably be the end of the story if some time ago he didn’t meet with a friend of mine, happening to also be a friend of his, whom he told the story and offered to just take the phone and keep it if he manages to fix it. “Sure, why not!”, said my friend, and the story went on. Quite a few repair shops later he finally found a place that would take it in for repairs. But when he came back two weeks later to pick it up, he was to find out that “they fixed the button but the phone itself now is not turning on and not charging”. And they even had the audacity to demand payment for their work. No, really.
So the next time we met, he told me the story and asked me if I could do something about it. Surely enough, not long after we were looking at the guts of the device (here I need to mention that the dual sim model is much easier to take apart when compared to its original single sim version). Even less time it took us to find the reason for it not charging – the cable coming from the USB board was not actually inserted and locked in place. We also found evidence of some parts being put together not in the correct order.
Having given it some time to charge, we attempted to turn it on. The phone came on and booted into the OS. “Great, it works!”, we thought. “Not yet”, thought the phone and 5 minutes later went into boot loop, which could only be stopped by disconnecting the battery or unclipping the power button connector from the motherboard. This is how we learned that the button was never fixed either.
Now we get to the point that is probably the main reason you’re reading this. Researching the topic online I have found many people having their HTC One (both M7 and the new M8) stuck in boot loop. To answer those questions – this is NOT a software problem, the problem is entirely in the power button unit, which is shorting out and constantly commanding an ON/OFF event, causing the phone to remain in the boot limbo.
To fix it, there are two ways. The first and the most obvious one is to go to eBay and buy a new button. There are many on offer, all within a tenner apiece. Once it arrives, you just pull the old one out of its bed (you are NOT required to disassemble your phone for this beyond just the back panel removal), replace it with the new one and you’re good to go.
However, there is a 90% probability that you can just fix the old button, and it will only require some cleaning alcohol (Vodka would do too) and a toothbrush. You will need to remove the bit of isolation next to the connector, which will reveal to you the tiny board underneath. On the picture above you can see what it’s supposed to look like when new. Yours, most likely, is going to be heavily oxidised, evident by white flakes and stains over it. Your task is to take the alcohol and the brush and clean them off. Leave the whole piece in the alcohol for a few minutes, then brush it not too forcefully, then soak again for a bit, then brush again. Repeat until you’re happy with the result. You won’t get it back to the ‘like new’ state, but it should be clean enough to eliminate the source of short-circuiting.
Let it dry, install it back, put the rest of the phone together and enjoy your HTC being back to life.