Marantz CD6005 - USB;iPod Playback Troubleshooting; No Sound from USB;iPod

3.3. No sound is output when a USB, iPod is played back
Is the CUP12551 MAIN B'D connector disconnected?
• CWC100, CWC101, CN1101, N2101, N2801
Is the CUP12551 MAIN B'D USB DSP IC power supply normal?
• IC105 9pin, 14pin, 22pin, 39pin, 43pin (+3.3V)
No sound is output when a USB,
iPod is played back.
Is the USB DSP IC reset signal of the CUP12551 MAIN B'D input as
High (+3.3V)?
• R118
Is the USB DSP IC digital communication signal of the CUP12551
MAIN B'D normal?
• R198 (USB_RTS)
• R199 (USB_CTS)
• R200 (USB_SO)
• R201 (USB_SI)
(For details of the control waveform, see "3.4. USB DSP
Communication Waveform".)
Is the USB data (+/-) signal to the USB DSP IC of the CUP12551
MAIN B'D normal?
• R213 (DP)
• R212 (DM)
(For details of the control waveform, see "3.5. USB Data Waveform".)
Is the USB DSP IC digital input signal of the CUP12551 MAIN B'D
normal?
• IC102 13pin (USB_DATA)
• R16 (USB_BCK)
• R23 (USB_LRCK)
(For details of the control waveform, see "2.2. FLD Control Waveform".)
Insert any disconnected connectors.
YES
Check the regulator (U3901) +3.3V_D of the
CUP12552Z_A-3 POWER B'D and the circuits and
soldering that handle the output load, and replace any
faulty parts.
Check the USB DSP circuit of the CUP12551 MAIN B'D
and the circuit and soldering that handle the output load,
and replace any faulty parts.
Check the following IC of the CUP12551 MAIN B'D and
the circuit and soldering that handle the output load, and
replace any faulty parts.
• U1101(19pin, 34pin, 37pin, 38pin)
• U2001(6pin, 7pin, 8pin, 85pin)
Check the following IC of the CUP12551 MAIN B'D and
the circuit and soldering that handle the output load, and
replace any faulty parts.
• IC105(40pin, 41pin)
Check the following IC of the CUP12551 MAIN B'D and
the circuit and soldering that handle the output load, and
replace any faulty parts.
• IC105(31pin, 32pin, 35pin)
• IC102(13pin)
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
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