MOMOH
New member
Have got an 820-3115 , with no cpu activity . the machine goes on and the DRIVE LED REMAINS ON . I could not pick up anything except that L7550 is 0V , schematic says should be 1.5V. So am not sure if that is my problem or that the signal is not present because the board is not posting ...Also R7555 is 0V on both sides , am not sure if thats okay as well. did replace U7400 , but nothing changed