Aftermarket USB car and home chargers even if their rated at 1 amp will charge the the battery at .5 amps. Samsung and several other phone manufacturers put a jumper across the 2 center data leads to tell the phone to charge at 1 amp. Aftermarket chargers don't have this jumper, the phone detects this and charges at .5 amps. You can tell if it is charging at .5 amps by going to settings>battery. If it says CHARGING USB it is only charging at .5 amps. If it says CHARGING AC it is charging at 1 amp. Verizon car chargers have this jumper and will charge at 1 amp.
Interesting. I'm sure I'll plug in my device at some point tomorrow and I'll check that. I have a feeling its USB mode because even my standalone GPS thought it was hooked up to a PC at first. Definitely the adapter then as a normal car charger works fine. Thanks for posting that info, that hadn't crossed my mind
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