Kyocera 6035 on Sprint service. It will work sometimes, Full battery, half battery no difference. Phone will be on & working fine. After an undetermined amount of time, Not touching the phone the phone part just shuts down. PDA works fine. Holding the power button, it starts to power up, Sprint Logo Splash screen shows up, you will see a power on statement flash, then goes to power off. Multiple attempts to get it to come on, to no avail. Sometimes, not always, leave it alone for a while (6-12 Hours) now it will work again for a while. Any suggestions out there?