No Sound From Headphone - Technics SU-G700E Service Manual

7.13. No Sound from Headphone

No Sound from Headphone.
Is the correct voltage
presented at P2901 on Headphone PCB?
Between Pin 6 and 5:
Headphone Inserted: +3.0 or over
Headphone NOT Inserted: +0.1V or lower
Is the correct voltage
presented at P6502 on AMP PCB?
Between Pin 14 and 26:
Normal: around 3.3V
Replace Main PCB.
YES
Is there a connection
between Main PCB and AMP PCB?
Pin 19 of P4552 and Pin 4 of P6801
NO
YES
NO Is there a connection
between AMP PCB and Headphone PCB?
Pin 6 of P6801 and Pin 6 of P2901
NO
YES
Is FFC between
P6503 on AMP PCB and
P4552 on Main PCB
damaged?
Replace FFC.
Replace FFC.
30
YES
Replace Headphone PCB.
NO
YES
Replace AMP PCB.
NO