Marantz NR1504 /U1B Service Manual page 85

5.2. USB device is not recognized
Are you using a USB hub?
Is the USB device compatible with the set?
Is the wire properly connected between N2801 on the HDMI board
and CN4401 on the USB board.
Is a voltage (5V) supplied between the pins 1 and 4 of CN4401 on the
USB board (USB connector)?
The circuitry from U2602 on the HDMI board to CN4401 on the USB
board is defective.
5.3. No picture or no sound is output
Are digital video signals(BCLK, VD0 - VD7) output from U2602 to
IC1600?
Check the HDMI/DVI circuit.
Are S/PDIF signals output to U2203 pin 31?
Check the Digital audio circuit.
Checking the USB device
NO
YES
Checking the set (NR1504)
YES
YES
Checking the set (NR1504):(If no picture is output)
YES
Checking the set (NR1504):(If no sound is output)
YES
YES
Don't use the USB hub.
Only mass storage devices in FAT16 or
NO
FAT32 format or MTPcompatible devices
and iPod (Remove some models) are
supported.
NO
Connect the wire properly.
NO
The U2806 and surrounding circuitry on the
HDMI board are defective.
NO
U2602 and surrounding circuitry are defective.
NO
U2602 and surrounding circuitry is defective.
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