Poor LCD
Display
JADEVER SCALE CO., LTD
LCD defective
After confirming that there is no broken board
line or short circuit of connection between
LCD and other conduction objects, please
directly replace LCD.
Component or part
Please check CP19/LM2930 , then replace
defective
the defective one.
IC(PT6554) related circuit
Please check IC (PT6554) related circuit
fault
fault, replacement is needed for the defective
one.
Incorrect
weighing
buzzer
Component
LM2931,AD5530 or
4.9152M is defective
Load cell Malfunction
Q11 or Q8 defective
Replacement is required
Replacement is required
Please check / replace Q11 or Q8
does not work
BUZZER defective or
buzzer circuit fault
Replacement is required
Keypad
dysfunction
Memory
dysfunction
messy code
occur in the
print out
copies
Keypad or keypad circuit
fault
CPU / CPU program
effective
Component 74LS139
defective
Component
24C02,R29,R30,R31 or
CP18 defective
Wrong setting
Check/replace keypad or keypad circuit.
Check/replace CPU
Check / replace component 74LS139
Please check 24C02,R29,R30,R31and
CP18,then replace the defective components
Please check /reset external device/ baud
rate/print mode(refer to 3-3)
RS-232 board defective Please check/replace RS-232 board.
Bad connection between
RS-232 board and main
board
Defective in external
device
Please check/replace the wire connection
Maintenance/replacement is need.
18 JCL Service Manual