16
XW-NAC3-K
1
2
3
4
A
B
C
D
E
F
1
2
3
4
5. DIAGNOSIS
5.1 DIAGNOSIS FLOWCHART
No power
• Checking the voltages for
V
+B and SIG
N
AL PO
W
• Checking the voltage
of AT+3.3
V
N
o
N
o
N
o
• Checking internal cable connections
Yes
Yes
• Checking the PO
W
ER PCB Assy alone
Yes
N
o
• Checking the voltage of AT+3.8
V
Yes
• Checking that the microcomputers are reset.
N
o
N
o
Yes
Yes
• Checking if a protection circuit was activated.
• Checking that the main clock for
the microcomputers is oscillating.
N
o
• Checking ACDET
Yes
N
o
Yes
Plug the power cord in (Standby mode).
Are
V
+B
and SIG
N
AL PO
W
nearly 14
V
?
• Check that IC1701 and its
peripheral parts are not
damaged.
• Check that the line for AT
+3.3
V
is not short-circuited.
Is AT+3.3
V
nearly 3.3
V
?
Is Pin 90 of System
Ucom (IC1000) nearly
3.3
V
?
Is X1001
• Check that the path between Pin 1
of CP1700 and Pin 81 of System
Ucom (IC1000) is not broken or
short-circuited.
• Replace the PO
W
ER PCB Assy.
Is Pin 81 of System
Ucom (IC1000) nearly
3.3
V
?
Check that System Ucom (IC1000)
and its peripheral parts are not
damaged.
Is AT+3.8
V
nearly 3.8
V
?
Check that D1705 is not
damaged.
Check the protection
circuits.
Check
Pin 83 (P_O
N
_Key),
Pin 55 (Key1), and
Pin 74 (REMOCO
N
)
of System Ucom (IC1000).
Perform connections
properly.
Replace the PO
W
ER
PCB Assy.
Check that +B and SIG
N
AL PO
W
on the
MAI
N
PCB Assy are not short-circuited.
Are the cables
properly connected?
Is the
output from the
PO
W
ER PCB Assy
14
V
?
Remove the PO
W
ER PCB Assy to check it alone.
Press the PO
W
ER key.
Check that IC1001 and its
peripheral parts are not
damaged.
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TEL 13942296513 QQ 376315150 892498299
