No matter what you do, you can't get your phone to turn on.
The Nokia N70 uses a 3.7V Lithium ion battery which should, in theory, only use up to 20% capacity per year; however, this percentage can vary with temperature. The depletion of the capacity of a battery can be mistaken for manufacturing problems; however, the solutions for each are the same: Installing Nokia N70 Battery
The manufacturing of a battery can be considered faulty and the occurrence of this is not rare. If you are certain that the battery is not holding optimal capacity, then the battery can be replaced.
Before throwing your cell phone out the window, ... please read on
A speaker can be subject to improper manufacturing or by disconnected terminals caused from daily use. In either case the phone can be taken apart and the speaker can be replaced: Installing Nokia N70 Speaker
More times than not, the lack of sound coming from a speaker can be fixed by simply un-muting your phone. See your device manual or follow the link to the on-line Nokia N70 Device Manual
The Nokia N70 uses a 2 MP camera and supports LED flash. If the images taken from the camera are lower than expected quality or the camera does not function properly then the camera can be replaced: Installing Nokia N70 Camera
If your keys aren't working, it is possible that the keypad may need to be replaced.
Keyboard problems can be caused from being multiple issues which can either be caused faulty wiring, or dust being that might obstruct the keyboard from operating.
The keys on your keyboard can be stuck due to dust and grime due to daily use and can be fixed through a disassembly and proper cleaning.
The unresponsiveness of a keyboard can be caused to faulty wiring connections which can cause the keyboard not to work entirely. The keyboard can be disassembled and then the connections can be fixed, or the entire keyboard can be replaced: Installing Nokia N70 Keypad
It is possible that the screen display is not working due to the following causes:
A cracked screen can cause the LCD display to not function properly. In this case, a new screen should be installed: Installing Nokia N70 Display