I noticed that plugging my Samsung Galaxy Nexus phone into the USB port that it does not seem to charge much, if at all and in fact may be losing charge. Has anyone else experienced issues charging via the USB ports? I'm guessing that the USB ports don't put out all that much current, though it's enough to drive a USB-powered 1.8" hard drive. I'd prefer to not have to use my 2A aux port USB adapter if possible.
My Iphone charges fine from the USB port (closest one to passenger side - but I think both are the same. The other always has my music usb in it). In fact I think it charges even when the car is off.
I've noticed that my iPhone will charge from the USB port, but it charges much quicker if I use the 12v "cigarette" port with an adapter.
I'm pretty sure the USB ports put out the standard .5 amps, so a 2 amp cigarette charger is going to be a lot faster.
I was originally told by my DS that they were 2A ports, but this isn't the first time I've read observations they don't seem to be.
And I was told to use a 12V adapter when charging a tablet. And beware, many, if not most, 12V USB adapters are crap that themselves don't put out a proper 2.1 amps that an iPad wants. The 12V port, BTW, turns off when the car is "off" (ie no one in it). It would have been nice if Tesla actually had USB ports that would work with tablets, but at least cars up until about VIN 6000 (my car), the USB ports cannot power a tablet. After reading reviews on Amazon, I just recently bought an Anker, 18 total watts, 12V USB charger.
My Verizon Blackberry (Bold?) I got from my employer a year ago won't charge from most rental car USB ports or my 1A 12V adapter but does take a charge from the Model S USB ports. iPhone 5 works fine on all of them. ----- updated ----- Not only am I able to charge an iPad from the USB, I successfully used an Apple MagSafe airline adapter to power (don't think it can charge) my MacBook Air. Apple says it's for use in planes only which are 15V but it worked for me in the Model S and didn't in our minivan.