ubuntu-phone team mailing list archive

[Pat McGowan <pat.mcgowan@xxxxxxxxxxxxx>]

A number of folks have experienced getting their Nexus 4s into a state
where they will not turn on and they will not charge. The device seems
to have a deep sleep or hibernation mode that it enters on very low
battery conditions. The following steps are known to work and come from
the google forums.

Note that an issue in the qualcomm sensor driver was recently worked
around to release a wakelock that was preventing the Nexus 4s from
suspending normally and therefore depleting the battery. This fix is
currently available in the pending release.

"To bring the Nexus 4 out of hibernation:
1. Plug Nexus 4 to a wall charger.
2. Press and hold the Power button for 60 seconds
The device should now turn on."

Note that the red light will come on to indicate charging with low
battery level. After a minute or so the battery icon will appear then
screen will blank to indicate normal charge.

Reports are that 10 secs is sufficient to force the phone from deep
sleep to off.
We have also seen recovery after allowing the battery to completely run
out also causing the phone to be fully off. Then plug it in, red light,
and happiness.

The following technique was also recommended but generally did not work
for us in the hibernation state.

"If customer has let Nexus 4 battery run all the way down and it will no
longer charge, have customer try the following:
1. Plug Nexus 47 to a wall charger.
2. Immediately press Volume Down and Power at the same time to reach the
bootloader
3. From bootloader menu, press Volume Down until you see "Power Off Device."
4. Press the Power button to select the 'Power off device' option
5. Once your device is off, unplug the charger and then plug it back
into the device.
The device should now begin charging correctly."