Service manual
49
DV-NC55U/C/M
FLOW CHART NO.17
NO
Check the peripheral circuit of front input terminal.
L-ch
R-ch
Front input terminal
Rear input terminal
YES
NO
YES
YES
NO
NO
Tuner audio terminal
YES
YES
NO
NO
NO
NO
Check the peripheral circuit of rear input terminal.
Check the regulater circuit of Hi-Fi 5V and PC 9V.
Replace IC1651.
NO
NO
NO
NO
Is there signal inputted at each
terminal of IC1651 as shown in table?
pin(15) pin(10)
pin(14) pin(9)
pin(48)
Is the voltage 5V applied to pin(40) of IC1651,
9V applied to pin(58).
Are serial data and clock signal at pins(43),
(42) of IC1651?
Line output terminal connection
Is the audio signal output respectively to the pins(53)
and (57) of IC1651?
Is "L" level applied at pin(36) of IC1651?
Is "H" level applied at pin(45) of IC1651?
Check line between pins(43), (42) of IC1651
and pins(17), (18) of IC1701.
YES
YES
NO
Is the audio signal input respectively to the pins
(13) and (1) of IC6010?
Check the line between the pins(53) and (57) of
IC1651 and the pins(13) and (1) of IC6010.
YES
Is the audio signal output respectively to the pins
(7) and (1) of IC6011?
Is 9V applied to the pin(8) of IC6011?
YES
YES
Check the AUDIO OUT terminal (J1202) and the
line between the pins(7) and (1) of IC6011 and the
AUDIO OUT terminal (J1202).
Replace IC6011.
YES
NO
NO
Is the audio signal input respectively to the pins
(5) and (3) of IC6011?
Check the line between the pins(14) and (15) of
IC6010 and the pins(5) and (3) of IC6011.
YES
NO
Is the audio signal output respectively to the pins
(14) and (15) of IC6010?
Is 9V applied to the pin(16) of IC6010.
Are the pins(9), (10) and (11) of IC6010 on "H" level?
YES
Replace IC6010.
NO
Check the DVD-H line and Q6010.
Check the PC 9V line.
Check line between pin(36) of IC1651 and
pin(21) of IC1701.
Is Sub carrier signal (3.58MHz, about 900m
Vp-p) input to pin(45) of IC1651?
Check line between emitter of Q1501 and
pin(45) of IC1651.
YES
Check the line between the pin(59) of IC1651 and
the pin(2) of the tuner (TU1101).
RF output terminal connection
Is the audio signal output to the pin(59) of IC1651?
Is there SIF signal from pin(22) of Tuner?
No Hi-Fi E-E sound heard.
FLOW CHART NO.18
NO
YES
NO
YES
NO
YES
NO
Is terminal voltage (REC AGC. ADJ.) pin(37) of
IC1651 normal?
Is record FM signal output to the pins(21) to (24)
(ch-1)/pins(21) and (22) (ch-2) of IC1651?
Check the AH-MZ connector.
Replace IC1651.
Is the pin(29) of IC1651 about 3.7V?
Check Hi-Fi REC CTL line.
Is voltage 5V applied to pin(25) of IC1651.
Check line of Hi-Fi 5V.
Hi-Fi sound cannot be recorded (E-E mode is normal).
FLOW CHART NO.19
NO
YES
NO
YES
Is playback envelope signal output to the pins(29)
and (30) of IC1651? (300 mVp-p)
Replace IC1651.
Replace IC1651.
Is A-H.SW.P input into the pin(27) of IC1651?
Check the A-H.SW.P. line from the pin(27) of
IC1651 to the pin(26) of IC1701.
Hi-Fi sound cannot be played back (E-E mode is normal).
FLOW CHART NO.20
NO
YES
NO
YES
NO
YES
YES
Is audio signal input into the IC1201 pin(8)?
Is the pin(99) of IC1201 in "L" level?
Does the bias oscillation circuit operate normally?
Is audio signal on which bias signal is superposed
output to the pin(4) of IC1201?
Check the AA-MH harness and A/C head.
Check the bias oscillation circuit (T1601, Q1602,
Q1603).
Check the R1617.
Check the line between the pin(61) of IC1651 to the
pin(8) of IC1201.
Recording in linear audio is impossible (Hi-Fi E-E mode is normal).
FLOW CHART NO.21
NO
YES
YES
YES
NO
YES
NO
YES
NO
YES
Is it possible to confirm the audio signal (PB EQ)
on the pin(100) of IC1201?
Is audio signal output to the pin(11) of IC1201?
Check the line between the pin(11) of IC1201 to
the pin(62) of IC1651.
Are MH-AA harness and playback AMP. peripheral
parts normal?
Is the AC head surface clean?
Is AC head height adjusted properly?
Replace the AC head.
Readjust the A/C head height.
Is the pin(99) of IC1201 in "L" level?
Check the R1617.
Replace IC1201.
Linear audio playback is impossible. (Hi-Fi E-E mode is normal).