48
VC-A412U/A413U
VC-H812U/H813U
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
FLOW CHART NO.23
Is there signal inputted at each
terminal of IC651 as shown in table?
Front input terminal
Rear input terminal
Tuner audio terminal
L-ch R-ch
pin(15) pin(10)
pin(14) pin(9)
Check the peripheral circuit of front input
terminal.
Check the peripheral circuit of rear input
terminal.
Is there SIF signal from pin(22) of Tuner?
Line output terminal :
Check line ranging from pins(53) and (57) of IC651 to the audio output
terminal.
RF output terminal : Check line ranging from pin(59) of IC651 to pin(2) of tuner (TU101).
Is Sub carrier signal (3.58MHz, about 900m
Vp-p) input to pin(45) of IC651?
Is "H" level applied at pin(45) of IC651?
NO
Check line between pin(36) of IC651 and
pin(21) of IC701.
Is "L" level applied at pin(36) of IC651?
NO
Check the regulator circuit of Hi-Fi 5V
and PC 9V.
Is the voltage 5V applied to pin(40) of IC651,
9V applied to pin(58).
YES
YES
NO
Check line between pins(43), (42) of IC651
and pins(17), (18) of IC701.
Are serial data and clock signal at pins(43),
(42) of IC651?
Check line between emitter of Q501 and
pin(45) of IC651.
Line output terminal : Is there audio signal outputted at pins(53) and (57) of IC651?
RF output terminal : Is there audio signal outputted at pin(59) of IC651?
Replace IC651.
No Hi-Fi E-E sound heard.
pin(48)
Hi-Fi sound cannot be recorded (E-E mode is normal).
YES
NO
YES
YES
NO
NO
NO
Is record FM signal output to the pins(21) to (24)
(ch-1)/pins(21) and (22) (ch-2) of IC651?
Check the AH-MZ connector.
Is the pin(29) of IC651 about 3.7V?
Check line of Hi-Fi 5V.
Check Hi-Fi REC CTL line.
Replace IC651.
Is voltage 5V applied to pin(25) of IC651.
FLOW CHART NO.24
Is terminal voltage (REC AGC. ADJ.) pin(37) of IC651
normal?
Hi-Fi sound cannot be played back (E-E mode is normal).
Is playback envelope signal output to the pins(29)
and (30) of IC651? (300 mVp-p)
YES
YES
NO
NO
Replace IC651.
Replace IC651.
Is A-H.SW.P input into the pin(27) of IC651?
Check the A-H.SW.P. line from the
pin(27) of IC651 to the pin(26) of IC701.
FLOW CHART NO.25
Recording in linear audio is impossible (Hi-Fi E-E mode is normal).
YES
YES
YES
YES
NO
NO
NO
Is audio signal input into the IC201 pin(8)?
Is the pin(99) of IC201 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 IC201?
Check the AA-MH harness and A/C head.
Check the bias oscillation circuit (T601, Q602, Q603).
Check the line between the pin(61) of IC651 to
the pin(8) of IC201.
Check the periphery of pin(99) of IC201. (R617)
FLOW CHART NO.26
