2. The power cannot be turned on
(STANDBY LED is lit → light flashes)
Check insertion of each connector.
3. STANDBY LED flashes while using the unit
(Protection circuit becomes activated)
Malfunction of Selector.
[IC701, RLY701, RLY702, Q701, Q702]
Failure of the Volume circuit.
[IC702]
Failure of the MUTE circuit.
[RY1301, Q1370]
Failure of the power amplifier circuit.
Failure of the TONE circuit.
[RLY704, RLY705, Q730, Q731]
4. The power turns on but no sound is output
(both channels)
4.1. STANDBY LED not flashing (no protection operation)
4.2. Mute LED flashes when the volume is increased.
(Protection circuit is activated.)
Power LED flashes on for 0.5 seconds then off for 0.5 seconds, the
volume decreases and automatic recovery occurs.
Check insertion of each connector.
Check insertion of Input level and each connec-
tor.
Check the SPEAKER connections, SPEAKER short
circuit and SPEAKER resistance value.
After automatic recovery, if the protection circuit operates again when the volume is
increased again the STANDBY LED flashes 0.25 seconds on/0.25 seconds off.
TO "
5.2. I2C Communication Line Abnormalities
"
Check power supply voltage.
[CN103 : 1Pin] P3V3_UCON : +3.3V
[CN103 : 3Pin] +3.3VD : +3.3V
[CN103 : 5Pin] +5V_LEGO : +5V
[CN102 : 1Pin] +5V_USB : +5V
[CN102 : 7Pin] +5V_DAC : +5V
Check connector is properly attached. If there
is no problem, one of the parts listed below is
malfunctioning.
・MAIN PCB [IC718] P3.3V_UCON
・MAIN PCB [IC716] +3.3VD
・SMPS PCB [IC1823] +5V_LEGO
・SMPS PCB [IC1822] +5V_USB
・MAIN PCB [IC714] +5V_DAC
NO
YES
Is there an input signal from OPT1/2 and COAX
to the DIR terminal?
[IC107 : 32Pin] OPT1
[IC107 : 33Pin] OPT2
[IC107 : 37Pin] COAX
Is DIR outputting the following signals?
[IC107 : 17Pin] DIR1_DATA
[IC107 : 18Pin] DIR1_LRCK
[IC107 : 19Pin] DIR1_PBCK
[IC107 : 20Pin] DIR1_MCK
YES
Failure of OPT input terminal [JK101, JK102].
Malfunction of [IC109, IC121].
Malfunction of [IC107].
NO
NO
NO
Is there a DAC input/output signal?
[IC115 : 8Pin] I2C_SCL_DAC1
[IC115 : 9Pin] I2C_SDA_DAC1
[IC115 : 25Pin] AK449
[IC115 : 26Pin] AK4490_R_OUT-
[IC115 : 35Pin] AK4490_L_OUT-
[IC115 : 36Pin] AK449
4. The power turns on but no sound is output
No input signal
・Malfunction of [IC101 or IC116].
Input signal but no output signal
・Malfunction of [IC112 or IC115].
YES
YES
5.1 DIGITAL BLOCK Power Supply Voltage Abnormalities
5.2. I2C Communication Line Abnormalities
Before Servicing
This Unit
Electrical
Mechanical
Repair Information
Updating
44