Defect Of Amp Circuit; Defect Of Power Supply Circuit To Amp - Sony MHC-GPX5 Servise Manual

1.

Defect of AMP circuit

1-1. If PROTECT mode is "AMPLIFIER",
The following defect might be possible.
Defects Possible cause
Unusual heat up of MOSFET by im-
OTP (Over Tempera-
proper assembly of heatsink, destruction
ture Protection)
of MOSFET etc..
DC appears in SP terminal by defect of
DC Detection AMP IC and MOSFET or output is short-
circuit.
Unusual output of
The power mount has unusual output.
Power mount
1-2. If speaker does not have output even if the set status is not
in PROTECT mode
The following defect might be possible.
Defects Possible cause
Under Voltage IC1402 output is below 12V.
RESET defect Reset signal status from micom is not 'H'.
2.

Defect of power supply circuit to AMP

2-1. If the PROTECT mode is "POWER SUPPLY",
There is possibility of unusual power supply of any of the
AMP IC or Pre-amplifi er.
• To release from this mode.
Press [ ] button and [
u
again or unplug and re-plug in the power cord.
] button simultaneously
x
HCD-GPX5G/GPX7G/GPX8G
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