No sound from the Panel speakers (1/2)
No sound from the Panel speakers Yes Is the sound muted? No Is the volume set to "0"? No Are the headphones connected? No Is only the sound of TV not output? Yes Is the signal output from FE (U4401)? (pin 18) 24 Yes Are the signals output from IC4401? (pin 30), (pin 31) 25 Yes Are the signals input to IC4804? (pin 19), (pin 20) Yes Check around IC4804 and communication between IC4804 and the microcomputer. Is only the sound from the front input not output? No Is only the sound from the external input not output? No Yes Check between pin jack and IC4804. No Check between IC4401 and IC4804. No Check around IC4401 and communication between IC4401and the microcomputer. No Check around FE (U4401) and communication between FE and the microcomputer. No Is only the sound from the HDMI connector not output? Yes Are the signals output from IC6405? (pin 7), (pin 8) 27 Yes Are the signals input to IC4804? (pin 10), (pin 11) 28 Yes Check around IC4804 and communication between IC4804 and the microcomputer. No Check between IC6405 and IC4804. No Check around IC6405 and communication between IC6405 and the microcomputer. No Yes Disconnect the headphones and check the sound from the speakers again. Yes Yes Cancel muting and check the sound with the headphones again. Raise the volume and check the sound again.
A
B
C
26
D
Yes
Check around pin jack and communication between CN4001 and CN7804.
