phone won't turn on

There are several reasons why your phone will not boot up. The first is a bad battery, the second and more popular reason is that your charging system is failing and the battery simply is not truly getting charged enough to boot the phone. However there is one other reason for all this. You mentioned your phone is rooted with a modified ROM. Sometimes the computer that is responsible for telling the phone how much charge the battery has gets confused and reports the wrong information to the phone. So, the phone thinks that the battery is to weak to boot the phone. Etradersupply.com helped me fix a similar issue by explaining to me about borrowing a friends fully charged battery. After installing it I was able to get in and reflash my ROM. Then once completed I restored my old battery and what do you know. It showed charged and the phone accurately registered the battery charge and so when I charged it it would take a full charge. Turns out it was a simple glitch that I might have been able to fix from the settings on the ROM if I could have booted the dang phone. There are other reasons that would cause this, some are due to hardware failure but it never hurts to try the simple fixes first.

We just wanted to follow up with some additional steps you can try. Before completing any more steps, please check of the device has any sd cards in the sd slot. If it does please remove it before proceeding. After removing the sd card please re-attempt to boot the device. If does not work the next steps involving wiping the device. However this will result in unrecoverable LOSS OF DATA.

If you have not already done so please download and install Kies to your computer. After installing connect your device to your computer via your USB cable. Wait to see if Kies recognizes your device. If it does then proceed to the next step.

1 Open Kies 3 and click Tools > Firmware Upgrade and Initialization.

2 Enter your device Model name and click OK.

3 Enter the device IMEI number and click OK.

4 Kies 3 will verify that the feature is available for your device. If the feature is available, click OK to continue.

5 The firmware version is displayed along with a note that the information on your device will be permanently deleted during this process. Click OK to continue.

6 Follow the steps to prepare your device for emergency recovery. Mark the checkbox next to I have read all of the above information. Select whether you agree to share this update with Samsung. Connect your device to Kies when you have activated the download mode. When your device is in download mode and connected to Kies 3, the Start upgrade button is available. Click Start upgrade to reinstall the firmware.

7 Touch Create backup to create a copy of selected items before proceeding. Touch Skip backup to proceed without backing up any items.

8 Kies 3 will download and prepare your system to update the firmware. This process can take some time. The time will vary based on your network and computer capabilities.

9 Respond to any security warnings about installing software.

10 The progress screen is shown during the upgrade process. The process will take several minutes to complete. Do not disconnect your device, turn the device off, or turn off your computer during this process.

11 Click OK when the upgrade is finished.

Thanks. ^Jake