Is the component soldered correctly?

Are the connected components (e.g. the corresponding legs of the microcontroller or GSM module) soldered correctly?

Once the phone successfully starts up, it will be locked and the screen will be blank. To unlock the phone, press any button; the date and time will scroll back and forth across the screen (this is the "unlocking" screen). If, during this time, you press the "unlock" key (the top-left button), the phone will unlock. The time will remain on the display, without scrolling. This is the home screen.From the home screen, you can lock the phone by pressing the left soft-key button (the upper-left button). The screen and backlight will turn off but the phone will still be on and able to receive phone calls or text messages.When the phone is in the "unlocking" screen, you can adjust the brightness by using the up and down buttons (the two central buttons of the group of four buttons just below the screen).You can dial a number from the home screen. Simply press the button corresponding to the first digit of the number. You'll be taken to the dialing screen where you can enter the rest of the number. Press * to delete the last digit entered or "back" (the left soft-key) to go back to the home screen. By pressing # one or more times in succession, you can enter #, *, or . To call the number, press the right soft-key ("call").From the home screen, press the down arrow (the lower of the group of four buttons just below the display) to enter the phone book. Use the down and up arrows to navigate to the desired entry. Press the right soft-key ("okay") to enter a menu from which you can call that contact, send a text message to that contact, add a new entry to the address book, or edit or delete the contact.To add a contact, first enter the contact list by pressing the down arrow from the home screen. Then press the right button to enter the contact menu ("call", "text", "add entry", etc); scroll (using the down and up buttons) down to the "add entry" menu item and press the right button. Now you can enter the name of the contact using the keypad (2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift). Once you've entered the contact's name, press the down arrow to move to the field for entering the contact's phone number. (You can press the up arrow to return to the field for entering the contact's name.) Enter the contact's number using the keypad (* is again backspace, but # now cycles between #, *, and ). When you've entered both the name and phone number, press the right button to save the contact (or the left button to cancel).To call a contact in your contact list, scroll to that contact, press the right button to bring up the contact menu ("call", "text, etc.) and then press the right button again to call. Texting a Contact To text a contact, scroll to their entry in your contact list and press the right button to bring up the contact menu. Scroll down to "text" and press the right button. Now you can enter your message using the keypad. (As for entering a contact's name, 2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift.) Press the right button to send the text (or the left button to cancel).If you find another component (e.g. the display, speaker, microphone, or buzzer) that's not working correctly, check: