First off, I want to say thank you for creating an amazing resource for these phones. I currently have a Galaxy S4 Active MF3. I bought the phone with the intent of using it in conjunction with my car stereo, which is a Pioneer 8500 BHS. I've paired this up with a Samsung MHL 2.0 adapter and ARLiberator. On top of this, I have installed a OBD-II bluetooth module in the car that also communicates with the phone. The end result is that the phone delivers full touch screen control of all apps on the phone, full bluetooth hands free calling, voice control, GPS (Tom Tom), Pandora, and most importantly, gives me a second dashboard where I can customize any gauge that the car did not offer stock, such as boost gauge, wideband air/fuel ratio, exhaust gas temperature, and a few other things. I'm using the full version of Torque to do this. It is amazingly useful, with one exception. The Samsung MHL adapter never lets the phone charge at more than 300 milliamps. The USB connection straight from the stereo charges at 900, and a 2.1 AMP charger with the Samsung cable will charge at 1900. However, regardless of the combination I use, the MHL always cuts this down to 300. This causes the phone to lose about 15-20% of it's charge every hour. For short trips, this is OK, but for longer trips, I can no longer use GPS, which is a big problem, as that's the whole reason I got the phone. Other users of the standard Galaxy S4 and this combination have been able to get around this issue by installing a ROM with Fast Charge enabled, which gives them 800 milliamps. This is just enough to let the phone be used and slowly charged at the same time.
I understand that currently we're limited to stock kernels with modifications layered on top (GoldenEye, ETC...), and that the Fast Charge code requires a kernel recompile in order to function. Is this correct? Do I have any other options? I've considered wiring in a wireless charger just to get the phone to charge on long trips, but I'm concerned that wireless charging in addition to the USB input and charge may cause the battery to overheat or reduce it's life.
Thanks in advance,