Brother LX-200 Service Manual page 175

15
Buzzer does not sound.
a. Defective buzzer circuit.
Problem Check Item
a. Defective Are 4kHz pulses output from
buzzer circuit DV0 (20 pin) on main
CPU#1?
Are correct voltages applied
across buzzer BZ1?
Buzzer BZ1 does not sound?
Cause
Defective main CPU#1. Replace Main PCB
assy.
Defective resistors R82 Replace Main PCB
and R83. assy.
Defective buzzer BZ1. Replace Main PCB
assy.
7-23
Remedy Repair
Replace
CPU#1.
Replace R82
and R83.
Replace BZ1.
See
Section
3.3.3
3.3.4
3.3.5
3.5.1