Panasonic KX-F900 Service Manual page 55

[- .... KX-FgO0 -]
(2) CHECK LCD ON THE MACHINE
If the digital board had broken, machine does not react at all and black square will be on the LCD.
There are 5 processes to display some letters (12:00 AM) on LCD.
I
If processes were not complete, black square will be on the LCD.
]
1. POWER ON
2. OSC
3. RESET
NG
If defective is in the power
line, LCD doesn't change.
NG
black square
4. Read the data in the ROM
(program start)
1
5. Make peripherals initial
NG
1,
NG
),
NG
J,
black square
black square
black square
LCD
J
LCD
IDDDD
LOD
IBDDD I
LCD
[FIDDD
LCD
L DDDD
-I
_0
0
r-"
m
-1-
0
0
-I
z
c:
o
m
LCD
12:00 AM
1
Monitoring (KEY IN)
1
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