The main fault voltage B1 is the normal 115V, field scanning block n301 (an5534) field pulse input pin 2 voltage by normal 1.1V into 0V, field output 10 feet from the normal 15V into 0V, the field power supply of VCC1 is 9V, VCC2, vcc3 is 30V. 2 feet down the measured integrated block n701 (an5095k) 58 feet (field pulse output voltage is normal) by 3.8V to 0V, the measured X radiation protection input pin 55 voltage by a normal 0V rose to 0.8V, the horizontal light because a component performance caused by bad, the gradual shift away from Fachade channel power supply overvoltage detection d431 zener diode (w04z15c) and 15V value is low, only 13.5V with digital transistor tester measured voltage value, and then connected in series with a 1N4148 diode in it switched on for three hours, the fault is no longer present, repair.A4Hservice manual download site