TROUBLE SHOOTING
YES
Is 12V obtained at IC251 pin#34?
YES
Is 5V obtained at IC251 pin#40?
Is Audio signal at IC251 pin#8, 9?
YES
Is Audio signal output at IC251
pin#19, 20?
YES
Is Audio signal output at IC602
pin #3, 13?
YES
Check Output JACK.
NO
NO
NO
Are CLK and DATA obtained at
IC251 pin#42,43?
NO
Check IC602.
19
Check POWER circuit.
Check Input AV2 JACK
YES
Replace IC251.