On Fri, 31 Jan 2014 06:59:53 +0000, Andy Burns wrote:

Does the phone detect the charger as capable of delivering high current?
If so, it should display "Charging A/C" instead of "Charging USB"
unless Samsung have hobbled that part of Android.

Hmmmmmmmm...... I never saw either "charging A/C" or "charging USB".

All I see is a lightning bolt and a percentage in the icon bar.
http://farm4.staticflickr.com/3755/1...d9fb71fe_o.gif

However, I just downloaded a bunch of battery-monitor apps to see if
they can help me identify the S3 battery drain problem.

In addition, googling, I found this disturbing reference:
http://forums.androidcentral.com/t-m...p-charger.html
Which says:
"a lot of 2A chargers are designed for iDevices and their weird way of the
charger signaling to the device that it is ok to draw max power. Absent
fairly specific voltages on the data lines iDevices will either assume they
are connected to a computer and only draw 500mA, or they won't charge at all.
However, most non-iDevices simply look for the two data lines to be shorted
together to let them know they are connected to a dedicated high power charger
and not a computer. That means that most non-iDevices will not recognize 2A
chargers that are designed for Apple products as being high-power and so the
phone will only draw 500mA even hooked up to a 2A charger."

If that statement above is true, then my reputed 2.1 Amp car USB charger
could only be sourcing 500 mA to the Galaxy S3.