Acer AL1751 AL1751 Service Guide - Page 33

2. No picture (LED is orange) No picture NG Key is under control? OK X401 oscillate waveform is normal X402 oscillate waveform is normal NG Replace X402 OK Replace U402 OK NG Replace X401 NG Check if the sync signal from computer is output and video cable is connected normally Replace U401 NG OK Replace U401 Input the sync signal of computer, or change the cable 33