Nokia 1800 keypad solution

Nokia 1800 keypad solution is useful for nokia 1800 phone.Keypad can be two kind of problem one key single dose not work and the other problem is key not working solution work.Single Carbon light on the keyboard. And no button not working solution is to display the image below . How : If complete pcb, you encounter this problem first then clean with the divine essence and ways to check the keyboard line .