Switch Board Function Failure - NEC Barracuda Service Manual

8.8 Switch Board Function Failure

Symptom:
Switch Board Function is not working property when pressing the button.
J1
VCC_3VSB
P4
R400
100K
D18
SW4
1
3
2
C120
KEY8
D19
0.1U
SW5 16V
1
3
2
C121
KEY8
0.1U
D36
16V
SW8
1
3
2
C124
KEY8
0.1U
16V
SW2
C118
KEY8
0.1U
16V
SW3
C119
KEY8
0.1U
16V
D20
SW6
1
3
2
C122
KEY8
0.1U
16V
D26
SW7
1
3
2
C123
KEY8
0.1U
16V
D37
SW9
1
3
2
C125
KEY8
0.1U
16V
Barracuda PDA Maintenance
VCC3
J19
R388
P16
10K/1%
BUTTON_DET
0.1%
R395 R396
R397
0
4.02K/1%
20K
0.1% 0.1%
0.1%
BT_TASKS#
BT_MEMO_PAD#
BT_FOURWAY_L#
VCC3
BT_FOURWAY_UP#
R398
BT_FOURWAY_DOWN#
100K
VCC3
VCC3
R399
R387
100K
10K/1%
BUTTON_DET1
0.1%
R392
R393
0
4.02K/1%
0.1%
0.1%
BT_CALENDAR#
BT_CONTACTS#
BT_FOURWAY_R#
MODEM/AUDIO
UCB1300
P11
43
IRQOUT
39
SIBSYNC
40
SIBDOUT
41
SIBCLK
42
SIBDIN
U42
VREF_1.25V
UCB1300BE
16
VREFBYP
C177
0.1U
R394
20K
0.1%
5
VSSD1
37
VSSD2
18
VSSA1
7
VSSA2
26
VSSA3
UCB1300BE
P4
UCB_IRQ
SFRM_C
RXD_C
SCLK_C
TXD_C
U3
Intel StrongARM®
SA1110
Microprocessor
KEY_PRESS#
137