There is no sound output by DIGITAL AUDIO AMP DAMAGE, repair the set according to the following guide.
1) Check FL±, FR± & SW± signals from IC602 to IC700 & 701 each input function. If no signal, check if I2S audio signals are entered to IC602.
2) Check PVDD. è If PVDD is abnormal, check the SMPS.
3) Check +12 V for driving the gate of AMP IC.
a. All the powers are normal, but if +12 V is low, there is possible for AMP IC to be damaged.
b. Remove L711, L712, L713 and L714 one by one.
When removed a inductance, if +12 V is recovered, AMP IC connected to it was damaged.
c. Replace AMP IC with a new one.
4) Check the impedance between IC700/IC701_OUT-A/OUT-B & GND.
a. If the impedance is 0 Ω, AMP IC might be damaged.
b. After removing the heat sink, replace it with a new one.
There is no sound output in the USB FUNCTION, repair the set according to the following guide
1) Check +5VU to USB board. If the USB LED are turned on, the voltage is okay, if so not, check +5.6 V to pin4 of CN501.
2) Check USB D± from MAIN board to USB board.
a. Check USB_DN/DP signals to IC801 (pin116, 117).
b. Check USB± signals from IC504 to CN501 (pin2, 3). If there is any trouble; check the power for each IC. The power is normal but, if the signal waveform to the IC is distorted or no signal, replace it with a new one.
3) Check if “Digital audio AMP block”.
There is no sound output in the AUX FUNCTION, repair the set according to the following guide.
1) Check AUX_L/R signals to IC401 (Pin7, 8).
2) Check if DAC_BCK, DAC_LRCK, & DAC_MCLK are entered from IC801 to IC401.
3) Check if ADC_DATA is entered from IC401 to IC801. If no signal, check +5 V & +3.3 V(ADC) for IC401. If is NG, replace it a new one.
4) Check the following I2S signal flow from IC801 to IC602. If there is any trouble, check the power for each IC. The power is normal but, if the signal waveform to the IC is distorted or no signal, replace it with a new one.
5) Check if the digital audio AMP block is okay. If AMP is damaged, replace it with a new one.
There is no sound output in the TUNER FUNCTION, repair the set according to the following guide.
1) Check if TUNER_LR is entered from Pin1,3 of TU100 to IC401(Pin23, 24). If no signals, Check +3.3 V for Tuner power. Check if the Tuner control signals (CLK, DAT, CE, RST, SLT) are entered from IC102 to TU100. If it doesn't work, replace TUNER with a new one.
2) Check if DAC_BCK, DAC_LRCK, & DAC_MCLK are entered from IC501 to IC202.
3) Check if ADC_DATA is entered from IC401 to IC801. If no signal, check +5 V & +3.3 V(ADC) for IC401. If is NG, replace it a new one.
4) Check the following I2S audio signal flow from IC801 to IC602. If there is any trouble, check the power for each IC. The power is normal but, if the signal waveform to the IC is distorted or no signal, replace it with a new one.
5) Check if the digital audio AMP block is okay. If AMP is damaged, replace it with a new one
When no sound output in the CD function, you cannot listen to music reading data from a CD disc if the pick-up module in MD doesn't work. This step is for checking the LASER FOCUSING ACTUATOR.
The focusing actuator makes the laser beam keep a regular interval with the surface of a CD disc.
1) Check the FOD signal from Pin13 of IC302. If no signal, check 3.3 V(RF) and X301.
2) Check F- & F+ from IC301 to CN301 for driving the focusing actuator. If no signal, check +1.8 V and +5 V for IC301.
3) Check if the FFC cable is solidly connected between CN301 and MD.
4) Check the MD. If the pick-up module has any trouble, it can not move the laser beam on the top or bottom side.
Please check the function after changing another MD.
The set doesn't work when press the power button on the front board or the remote control.
1) Check 3.7 V to CN304 and CN105 in standby mode. If there is no 3.7 V, check the SMPS.
2) Check 5.6 V, 12 V, F+, F- and PVDD when power on the set. If the set doesn't work regardless of what the KEY1 changes high to low while pressing the power button. X101 and X102 work normally but, if you can not power on the set, replace IC101 with a new one on the MAIN board.
