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-38-TroubleshootingQ5002Q5006Q5003Q5001Q50041210211415 338121312513Mute: HMute: LK8FK50BK10EP_SCLK2P_SCDA2AUD_PC/AV_SWVOLUMEMAIN BOARDAVBOARD IC5003AMP.IC5002VOLUMELRLRLRPCAUDIO-INAVAUDIO-INSP901IC1801OUTPUTEXPANDER<74LCX574>IC3551D/ACONVERTERIC301SYSTEMCONTROLPC AVAUD_PC/AV_SW at IC3551 H LAUD_PC/AV_SW at IC5001 L HAUDIO-SW Switching LogicMUTEIC5001AUDIO-SW<4052>+ 2 +489101113+-DATA BUS● Audio signal processing circuit● No SoundCheck AUD_PC/AV switching circuit.Check IC5001, audio-sw IC, and peripheral circuit.AUD_PC/AV_SW (PC:H) signal is applied on pin 10 of IC5001through Q5003, sent from pin 12 of IC3551.Is the audio signalobserved at pins 3 and13 of IC5001?Check Audio amp.and control circuit.Check IC5003, audio-amp IC, and peripheral circuit.MUTE signal (Mute:L) is applied on pin 4 of IC5003, sent frompin 12 of IC1801.VOLUME signal is applied on pin 2 of IC5002., sent from pin 13 ofIC3551.Check 5V_AUD power supply line.Is the audio signalobserved at pins 5 and8 of IC5003?Check audio output circuit.Check speaker, connection of the terminal “K8F”.YesNoYesNoCheck following steps. |
