Service manual

Page 34
MODEL: L423FR
3. No audio output generated.
3-1. No all audio output generated.
Raise volume level. And MUTE is turned off. Volume level is not 0. And MUTE is off.
YES
NO
YES
YES
Are the specified voltages available at the
pins below? (Power source check)
CN Name Pin No. Voltage
S5V J8A0 8 5Vdc
A5V IC8X0 8 5Vdc
A9V J8A0 3 9Vdc
S8V J8A0 7 8Vdc
AMPVCC J8A0 6 14Vdc
SAMPVCC
(PWB-DCDC)
IC870 2 14Vdc
Psave2* J8A2 3 3Vdc
Psave3** J8A2 4 3Vdc
*control signal of A9V, A5V
**control signal of AMPVCC, SAMPVCC
Problem is in the following
circuit (and peripheral
circuits) .
Voltage with
problem
PWB
including
the circuit
in problem
S5V DCDC
A5V MAIN
A9V DCDC
S8V DCDC
AMPVCC DCDC
SAMPVCC DCDC
Psave2 MAIN
Psave3 MAIN
NO
Poor harness connection or
defective cable.
NO
Is all harness connected correctly?
(Especially between PWB-MAIN and PWB-DCDC(J611-J6E4)
and PWB-DCDC and SPEAKER(J6EA-SPEAKER))
Enter audio input signal. ( ex. Component)
Problem is in IC601 or IC610 or their
peripheral circuits.
Please exchange PWB-MAIN
*When it cannot still fix, it may have a problem with SPEAKER.