LG TROUBLESHOOTING free download

File name TROUBLESHOOTING.pdf

ELECTRICAL TROUBLESHOOTING GUIDE (1) No Power. Any Key power on. YES NO Check power supply circuitry. Is power turnd on? Q808, Q809, Q802, IC401, PIN13 YES NO Check loading supply circuitry. DISC loading? Q505, Q506, Q507, IC401, CN505 YES NO Check laser circuitry. Does initial reading occur? Q501, IC501, IC503, IC504 Check focusing circuitry. YES IC501, IC503 Check DISC. NO Check tracking servo circuitry. Can disc be played? IC501, IC503 YES NO Check audio circuitry. Is audio output supplied? IC501, IC401, IC601, IC801 YES OK - 2-6 - (2) LCD light abnornal. Any Key power on. (without DISC) Power supply circuitry NO Check voltage in the power NO Do display LCD then light? defective. supply circuitry. Q802, Q807, Q808, Q809 YES Is u-com IC401 reset circuit NO Reset circuit defective. normal? Pin53 Q803,Q804 Surrounding circuit defective. YES Is u-com IC401X1, X2 terminal NO pin 57.58 input? X401, C410, C411 defective. OSC : 7.2MHz YES Is u-com IC401 keyin Pin17, 18 NO Q807, CN802 front PCB 5volt input? pattern defective.