HTC One M8 wont charge. Flashing/Faint Red Light

[Connor Kelly]

Phone is unable to charge with multiple chargers and wall plugs. It ran flat and has since been unable to charge. Different things have happened when the phone has been plugged in. Sometimes there is a flashing red light with a battery symbol on the screen. Other times there is a really really faint orange light. and others there is a flickering bright orange light then it will dissapear.

I am still under warranty but need the phone to power on to back up my data before sending it in repair.
Thanks in Advance

 

[Mooncatt]

I'm kinda in the same boat, only I'm already backed up and needing it to charge so I can encrypt/wipe it before turning in. It could be that the USB port could be bad on yours because you've tried the usual diagnostics and the phone is the only common denominator now. Mine had the port warrantied, but the replacement phone went bad too. I'm beginning to wonder if it's a poor design.

The flashing red LED (there's only red and green, no orange indicator) seems to mean that it is detecting the USB is plugged in but can't get enough connection to charge. I don't have any definitive answer for that, only what I'm guessing based on my experience with the flashing red LED.

My best advice is to first try getting a higher powered charger (either a standard 2.0A or QC2.0) and a high quality cable with thick power wires. Basically the goal here is to be able to feed as much juice with as little resistance as possible to the phone to hopefully overcome a shoddy port connection. Then very slowly and carefully try moving the plug around in the USB port. You may find that there's a spot where it'll make a connection just enough to indicate charging. In my case, pushing the plug down and to the left works, but pushing too much can break the connection again, not to mention too much pressure can damage the cable plug too. It'll take a lot of patience because the sweet spot can be very small and any movement of the phone/cable will drop the connection.

This has worked to some extent for me. Using the OEM 1.5A charger I found it'll indicate charging but the actual power level doesn't increase. In some cases it could even go down when the phone is off. Using a Samsung 2A tablet charger would push enough juice to overcome that resistance and charge to some extent. I can't say this will work for you 100%, but has been my best shot. If it's turned off, you may see a battery with a lightning bolt for a bit on the screen before actually going to the charge animation. If you can get it charged enough to power on, use Gsam or something to read current usage. I use Gsam, but it reads a positive charge current as negative numbers and discharging as a positive current for some reason. So be mindful of that, but it can help you fine tune that sweet spot. You could find that it'll show connected/charging but with a discharging current. As you work on it, with any luck you'll find a spot that connects and actually charges.

Best of luck to you.