I just purchased a new car stereo (JVC kd-r730bt). I knew it wouldn't be able to access my HD7's media through the USB, but the salesperson told me that I should still be able to charge through it. However, nothing happens when I plug it in. I thought it might just be my unit or a problem with the install, but I had the same problem when I went and tried it on the display unit in the store. The sales guy was at a loss. The only thing we could think of was maybe the unit doesn't have the right volts or amps for the phone? It does specifically say it charges 5V 1a, but another sales guy told me that most chargers are 1a and that shouldn't be a problem. Does anyone know what the issue might be and if there's any fix/work around for it?
By the way, I was able to charge the phone using the same USB cable with a different car stereo display unit (Pioneer deh-6400bt). It also charges just fine from my computer.
On the bright side, the JVC streams music beautifully from my HD7 over bluetooth. I'm glad I got it over the Pioneer even with the charging issue since the Pioneer only does phone calls over bluetooth not media.
Thanks for the reply, ninjaap, but I did switch it to usb manually and the phone still wouldn't charge. Also, the port seems to work either way, because my ipod charges no matter what the stereo is set on.
Oddly enough, the phone does turn on if it's off when I plug it in, so it must be getting some kind of current. Maybe it's just not enough or the wrong kind.
Thanks for the reply, ninjaap, but I did switch it to usb manually and the phone still wouldn't charge. Oddly enough, the phone does turn on if it's off when I plug it in, so it must be getting some kind of current.
...but probably not enough current. Over at Treo Central we had a list of chargers that would and wouldn't work with Palm phones.
1a should be enough, though. My Focus only needs 0.7a, and my Surround needs 1a. I imagine the HD7 only needs 1a. To find out for sure, you can check by looking at the specs on your HD7's power adapter (just make sure its an OEM adapter).
You could also try another USB cord, if you haven't already.
It didn't even occur to me to check the OEM charger, good idea. It says 5V and 1.0a so I guess that's not the problem. Now I have no idea what's going on.
And I just checked it with two other usb cables that charge my phone with my computer's usb. No dice.
Even though the specs say it has 1amp, that doesn't mean it's actually putting out 1amp. It's not unusual for manufacturers to later put out firmware updates to address issues. I'd email JVC support and let them know about the issue and i would also watch for firmware updates on their site: JVC Mobile Entertainment Car Navigation Updates
I would like to add, that not enough amps can still charge a device, just slower. I have an old Motorola Q charger that only puts out 550ma, but still charges my Focus. On the other hand, too much amps (in this case, over 1a) will not charge a device. I think it's a safety feature. So either it's putting out too much power or needs a driver update. My guess is leaning more towards an update, because your ipod charges okay.
Last edited by ninjaap; 03-11-2012 at 11:00 AM.
Reason: EDIT: oops I meant 550ma, not 550a