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ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the AUX Function, repair the set according to the following guide.
6-4. AUX FUNCTION
6-4-1. Solution
Replace IC301 on MAIN board.
6-4-2. How to troubleshoot (Countermeasure)
1) Check AUX_L/R signals to IC301 (pin1, 2).
2) Check if DSPI_BCK, LRCK, MCLK are entered from IC501 to IC301.
3) Check if ADC_DATA is entered from IC301 to IC501.
If no signal, check AVCC_3.3V & DVCC_3.3V (ADC) for IC301. If is NG, replace it a new one.
4) Check the following I2S signal flow from IC501 to IC601. (Refer to Item 6-2.)
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. Refer to “Digital Audio AMP” guide on Item 6-1.
If AMP is damaged, replace it with a new one.
6-4-3. Service hint (Any picture/ Remark)
< AUX function signal
fl
ow >
< MAIN board bottom view >
Pin15:DSPI_MCLK
Pin15:DSPI_MCLK
Pin16:DSPI_LRCK
Pin16:DSPI_LRCK
Pin17:DSPI_BCK
Pin17:DSPI_BCK
IC301
IC301