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LC-19A1E-BK/WH
4 – 4
Power supply (troubleshooting): A power supply does not come to each main circuit/IC. (3)
The power supply of a AUDIO system does not operate.
Checklist:
1) The check of the front page POW (1) is completed.
• • • UR12V is output to SC1204 (MAIN-PCB).
(If UR12V is not output, confirm the POW (1) again and repair.)
2) Check that BU3.3V is supplied to IC2002 (SUB-MICON), and the AC-CTL signal H is output from 35pin within a MAIN board.
(If BU3.3V is not supplied, check IC2004 (BU3.3V-REG) and a periferal circuit.)
3) Refer to attached sheet Power-Block diagram.
Is UR12V supplied to pin (47) (37) (13) (23) of IC303 (P-AMP)?
NO
Check the soldering of IC303 or exchange it.
YES
Is B3.3V supplied to pin (13) (26) of IC302 (A-CODEC)?
NO
Check the soldering of IC302 or Is B3.3V output from pin (3) of
IC703 (REG)?
IC703 (REG)?
YES
NO
Is UR12V supplied to pin (7) of IC703 (REG)?
Check the soldering of IC703 (REG) or exchange it.
Check the soldering of IC703 (REG) or exchange it.
Is B9V supplied to pin (14) of IC301 (A-SW)?
YES
Is B9V supplied to pin (38) of IC501 (AV-SW)?
NO
Is B3.3V output from pin (5) of IC702 (REG)?
NO
Check the soldering of IC702 (REG) or exchange it.
NO
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