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Troubleshooting a Canon PowerShot A720 IS
The Samsung SCH U470 (Juke) is a compact, lightweight phone with several features, including a swivel-hinge design, a VGA-resolution camera, and a 2 GB flash memory.
Note: This troubleshooting guide covers general problems with the Juke so you can identify what is wrong, then refer to repair guides to fix it.
The first thing to check if your phone won't turn on is if the hold switch is locked. If so slide the hold switch back to the unlock position and check the phone again for a response.
If you have a damaged or disconnected battery, your phone will most likely not be able to turn on, or may shut down periodically. The first thing to check is if the battery is fully connected to the phone. If the phone still fails to respond, try recharging your battery for a few hours and try again. If there is still no response you may have to replace the battery.
If the Juke has recently gotten wet, the problem may be water related. If this is the case, you may take apart the phone and let dry, then reassemble and try again. If the Juke still does not function, consider replacing the battery or logic board.
If you notice that on the Juke's display there are small black dots or large blots of what resembles ink, your LCD may have dead pixels or be cracked on the inside and "bleeding". There is not much you can do other than replacing your LCD screen.
If your screen is black or displays a blank colour then you may have damage with your logic board. You can check this by carefully disassembling the casing of the phone and examining it for any loose wiring or damage to the main board. If damage is significant, you should replace the logic board.
If your Juke has a dark or faint screen but the phone is still operating, the backlight may have burned out. To verify this take the phone apart and replay the LCD. If the problem persists there may be more significant damage to the phone associated with the logic board.
The first thing to do if you notice that your phone is restarting or shutting off on its own is to consider replacing the battery.
If you have replaced the battery and your phone still continues to restart or shut off, there may be issues with the circuitry of the logic board. Take the phone apart and check for any loose wires or damage to the board.
Upon noticing that your phone has frozen you should wait a few minutes to let the phone respond. If significant time passes with no response, remove the battery and reinsert it.If the problem persists replace the battery.
If you have replaced the battery and your phone still remains frozen, there may be a problem with the LCD display.