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Car charger can't keep up with GPS

M

Mister F

Newbie
I got a car charger with my phone but I never used it until recently. I was on a ski vacation with a friend of mine and at times we'd both have our phones connected to the car charger (one with two USB ports). He has a Galaxy S2. His phone would always charge quickly while mine would barely be a trickle. And that was with him running full navigation including GPS and screen, while mine would have all that off.

I recently got a phone mount so I can use navigation as well, and the charger can't keep up with the power demand at all. The battery drops like a rock even with the phone plugged in. Maybe it has something to do with the USB cable? Anyone have experience with this?

My One S is running Jelly Bean 4.1.1.
 
Is your car charger a HTC charger, eg. C300 ?

Tried you to switch the cable with your friend's ?
Your friend's cable might be a charge-only cable.

Harry
 
Nope I didn't try switching cables with my friend. I had no idea there was such a thing as a charge only cable. I have 4 USB cables and they all transfer data, so none are charge only. From what I've read, a data cable can only carry a current of 500 mA even if it's from a charger that can output more, and the phone will identify it as USB instead of AC. Still, when I have my phone plugged into a wall charger or the car charger, it identifies it as AC. And they don't seem to have a problem charging my Nexus 7 (which comes with a 2 A charger).

My car charger is generic - I got it at the Telus store with my phone and it doesn't show a brand or any specs. Based on that and what the Battery Monitor Widget is showing, I'm guessing it only puts out 500 mA. I've also plugged my phone directly into the car's USB port instead through the charger and it's the same result - can't keep up. I suppose the USB port is only 500 mA too. It sounds to me like it might be a combination of charger and cable.

I'm really surprised that the USB cables that come with every phone can't seem to carry enough current to keep up with intensive use. Nav seems like such a basic use for a phone.
 
I mentioned the HTC car charger because HTC, like other phone producers, follows the recommendation of USB standards for USB chargers ... they jump the data pins of their modified chargers for to bring the phone in 'AC charging' mode, means rapid charging with high amperage.
So you'd use a standard microUSB data cable to charge a phone in 'AC charging mode.

With generic chargers this modificaton with jumpered pins is rare feature to find.

Wikipedia: USB chargers with dedicated charging ports without data support

HTC car cargers come with a coiled cable which is a charge-only cable and is modified, means it has also the jumpered data pins in its microUSB connector.

In short, for rapid charging with high amperage, either you have to use a modified charger together with an USB standard data cable or a generic (not modified) charger together with a modified charge-only cable.
BTW, chargers should have 1A or more output amperage per phone and 2A or more per tablet.

Harry
 
Okay I think I've got it. I need either a 1 amp charger that jumps the data pins (which will work with a regular USB cable) or a charge only cable (which will work with a generic 1 amp charger). The wall chargers that came with my phone and tablet have jumped data pins so they work with a regular cable. And my friend probably had a charger that doesn't have jumped pins coupled with a charge only cable, which is why his phone charged and mine didn't.

There are plenty of 1 amp generic chargers out there but none of them say whether or not the data pins are functional. I found another HTC car charger, the CC200, which is half the price of the C300 but I can't seem to find any specs on it. Would it be safe to say it has those features? HTC 25531 Original Micro-USB Car Charger for HTC
 
I use the HTC car charger C200 and can confirm that the output amperage is 1A and charger and cable are both modified with jumpered data pins.

Harry
 
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