Denon D-T1 Service Manual page 43

6.4.2. Abnormality in BLUETOOTH
No sound is output from the BLUETOOTH input
source
YES
Check the Control Port of BT Module.
(check by switching the input to BLUETOOTH
and turning pairing on)
MAIN PCB
[U15 : 20, 22, 23, 24, 38, 42, 45pin]
20pin : Hi
22pin : "Lo" at Pairing ON.
23pin : "Hi" at Pairing ON.
24pin : Lo
38pin : Lo
42pin : The voltage changes from 1.2V to 3.3V
when playing audio content
45pin : Lo
Controlled as normal
YES
Check the Audio Line of [U13] output.
MAIN PCB
[U15 : 54, 55, 56, 57pin]
Audio signal is output as normal
YES
Check the OP-AMP of [U13] output.
MAIN PCB
[U13 : 1, 7pin]
Audio signal is output as normal
YES
Check the Audio signal Line of [U13] output.
MAIN PCB
[U13 : 1, 7pin] → [U17 : 5, 14pin]
NO
Go to "6.4.3. Abnormality in ANALOG IN"
NO
MAIN PCB
Check the connection of [U10 : 44, 51, 55, 52, 50,
56, 54pin].
NO
Check the circuits around [U15]. If there are no
abnormalities, there may be a defect in [U15].
(Change the MAIN PCB)
NO
Check the circuits around [U13]. If there are no
abnormalities, there may be a defect in [U13]
6.4.3. Abnormality in ANALOG IN
Check the Audio Line of ANALOG IN.
MAIN PCB
[P1 : 1, 3pin] → [U17 : 4, 11pin]
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