Service manual
FO-4400U
FO-CS1
(RESET)
(CHK_START)
(DFFSET)
(2-6C)
(+5V)
(+24V)
(DG)
(2-3C)
(2-6H)
(2-4H)
(2-1E)
(2-2E)
(2-3H)
(2-5H)
(2-5H)
(2-4H)
(2-5H)
(2-5H)
(2-5H)
(2-3H)
(2-5C)
(2-6A)
(2-6C)
(2-6C)
(2-6A)
(2-5A)
(2-6C)
(2-5A)
(2-5A)
(2-5C)
(2-5C)
(2-6H)
(2-2C)
(2-2C)
(2-2C)
(2-2C)
(2-2C)
(2-2C)
(2-2C)
(2-3H)
(2-3H)
(2-5H)
(2-6H)
(2-5H)
(2-6E)
(2-2E)
(2-3E)
(2-2E)
(2-6H)
(2-4C)
(2-3E)
(2-6E)
(2-6E)
(2-5C)
(2-6C)
(2-6E)
(2-2E)
(2-5H)
(2-6E)
(2-5E)
(2-4E)
(2-5E)
(2-2H)
(2-2H)
(2-3E)
(2-4H)
2
15
CMPVCC
80
ADVREF
74
DAVREF_P65
76
VSS
32
CNVSS
26
AN2_P75
6
P14
44
P04
52
P15
43
P16
42
AN4_P77
4
P10
48
P11
47
P05
51
P24
36
P12
46
P13
45
RESET
27
VCC
73
P25
35
P26
34
P03
53
P32
62
INT0_P42
25
P31
63
P27
33
P33
61
P34
60
RXD_P44
23
SCLK1_P46
21
P20
40
P21
39
P02
54
CNTR1_P55
14
P07
49
AN5_P60
3
AN6_P61
2
P35
59
P36
58
DA1_P56
13
P52
17
AN3_P76
5
DA4_P81
71
CMPIN_AN8_P63
78
CMPREF_AN9_P64
77
CMPOUT
79
RTP4_P86
66
PO1
55
PO0
56
INT4_P53
16
SIN2_P70
11
RTP5_P87
65
CNTR0_P54
15
SCLK2_P72
9
XIN
30
SOUT2_P71
10
AN1_P74
7
XOUT
31
P06
50
RTP0_P82
70
RTP1_P83
69
RTP2_P84
68
RTP3_P85
67
AN0_P73
8
P17
41
P40
29
P41
28
P47
20
P51
18
P50_TOUT
19
P37
57
P30
64
P23
37
TXD_P45
22
DA3_P80
72
AN7_P62
1
P22
38
P43
24
DA2_P57
12
AVSS
75
6
11
4
13
1
16
VCC
14
GND
7
COM
9
GND
8
3
14
3
4
9
8
VCC
14
GND
7
1
2
11
10
5
12
5
6
7
10
13
12
IC1B ULN2003ANS
C111
1000p
R102 4.7k
R107 33k
R139
4.7k
IC4
M38079EFFS_12MHZ
TP107
C135
1000p
C106
1000p
R131
4.7k
IC1F
ULN2003ANS
TP103
C109
0.1u
IC1D
ULN2003ANS
C133
1000p
IC1A ULN2003ANS
R109
11kF
C107
0.1u
RA6
820 x 4
RA4
820 x 4
R133 4.7k
C134
1000p
R134 0
C142 1000p
R115
1.5kF
C130
N.M.
N.M.
RA2
39 x 4
C104
N.M.
IC3E
TC74VHC02F
R120 100
R146 47k
IC1H
ULN2003ANS
R106
10k
Q100
DTB114EK
B
E
C
R148 33
IC1C
ULN2003ANS
C145
1000p
C152
1000p
D100
RB501V-40TE-17
C127 0.01u
R125 33
C114
N.M.
R123 10k
IC3A
TC74VHC02F
TP104
C136 1000p
R112 10k
C126 0.01u
Q104
DTC114YUA
B
E
C
TP101
R122
N.M.
N.M.
R121
C103
N.M.
C137 0.033u
R116
0
C100
C153 22p
R103
C128
22p
TP2
C155 0.1u
IC2B
SN74LS06NS
C122
C116 0.068u
C154 22p
TP106
C119
0.01u
RA1
TP102
C125
N.M.
C112 1000p
TP105
C121
N.M.
R104
N.M.
Q106
DTC114YUA
B
E
C
Q101
2SA1037
C3
N.M.
C151
1000p
R124 10k
R126 4.7k
RA3
4.7k x 4
R150 4.7k
IC2D
SN74LS06NS
IC2G
SN74LS06NS
R129 0
VR1
N.M.
R145 4.7k
R127
4.7k
R138
47k
R111 10k
D101
1SS355
R130 2.2k
C149
1000p
C150 1000p
R147
4.7k
IC2A
SN74LS06NS
R149 33
C131
RA5
4.7k x 4
R108
10kF
C146
1000p
C138 1000p
R136 33
R114
0
C108
N.M.
Q105
DTC114YUA
B
E
C
C105
1000p
IC2E
SN74LS06NS
IC3D
TC74VHC02F
Q102
DTD123YK
B
E
C
C113
0.01u
TP100
R135 33
X1
HC-49/U-S_12.MHz
TP1
C144 1000p
R113
2.2k
C102 1000p
C118
IC3C
TC74VHC02F
Q103
DTC114YUA
B
E
C
R140 33
C117
N.M.
N.M.
N.M.
R117
10k
R100
4.7k(F)
R132
R137
10k
C120
0.01u
R119 10k
R101
5.1k(F)
C143
N.M.
IC3B
TC74VHC02F
R141
47k
R143
10k
R128 10k
R110
2.2kF
R118 10k
C115 1000p
C129
N.M.
IC1E
ULN2003ANS
C147
1000p
R105
10k
C124 1000p
IC2C
SN74LS06NS
C101
N.M.
N.M.
C148
1000p
C110
R144 4.7k
IC1G ULN2003ANS
R142
4.7k
IC2F
SN74LS06NS
GND(DG)
+5V
GND(DG)
GND(DG)
GND(DG)
GND(DG)
+5V
GND(DG)
+5V
GND(DG)
GND(DG)
GND(DG)
GND(DG)
GND(DG)
+5V
GND(DG)
+5V
+5V +5V
GND(DG)
GND(DG)
+5V
GND(DG)
+24V
GND(DG)
GND(DG)
GND(DG)
+5V
GND(DG)
+5V
+24V
+5V
GND(DG)
GND(DG)
+5V
+5V
GND(DG)
+5V
GND(DG)
+24V
GND(MG)
+5V
GND(DG)
+5V
+24V
GND(DG)
+5V
GND(DG)
GND(DG)
+5V
+5V
+5V
GND(DG)
GND(DG)
GND(DG)
+5V
/FUSER_RL
/POLYGON_M_LOCK
/FEED3
/L_DATA
/PDATA
/POLYGON_M_CLK
/FUSER_LAMP
/SOS
M3_CLK
/MOTOR_REM
LD_POWER_LOW
/MOTOR_LOW
/MOTOR_LOCK
/PCURES
/FEED1
/PS1
/PS4
CHECK0
CHECK1
PS3
CHECK2
/UNIT
/P_EMP1
TONER_LEVEL
/2ND/3RD
/FEED2
/TONERLED_REM
/SH/H
/EPRDY
/PRRDY
/ETBSY
/TOD
/STS
/CMD
/SRCLK
/CTBSY
/CPRDY
/PRINT
2ND/3RD_SET
CH_LREM
T_MON_I
C_MON
T_MON_V
/FAN_REM
/LD_EN
2ND/3RD_SIZE
2ND/3RD_EMP
/POLYGON_M_REN
/HSYNC
/TEST
C_REM
B_VR
T_VR
FAN_LOCK
/M3_ON
TRAY_OPEN
THERMISTER
PS3_AN
P_EMP1_AN
MP_SIZE
/FAN_CNT
A
A
B
B
C
C
D
D
E
E
F
F
G
G
H
H
I
I
6 6
5 5
4 4
3 3
2 2
1 1
[3] Printer PWB circuit 1/2
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