11
+
4
Trouble shooting
Phenomenon
condition
Considerable cause
Check point/method
Remedy
AC power is not supplied
AC power is not applied to
switching power supply.
Is AC power plug connected to outlet?
Is outlet voltage normal?
Is fuse (primary side of switching
Power supply?
Is 24V output from secondary side of
switching power supply?
Connect the plug to outlet.
Replace the fuse
Replace the switching power supply.
Is DC power voltage
normal?
+5V is not generated.
Is D6 defect?
Is U1 defect?
Replace D6
Replace U1.
Crystal is not oscillating.
Check wave form pin 20 and
Pin 22 of U11(frequency 20MHz)
Replace crystal(x1)
Replace U11
Machine
doesn’t work
at all
Printer doesn’t work
after power on
The levels of PF lines don’t
become “H”
Is D2 defect?(open)
Is U12 defect?
Is D3 defect?(short)
Replace D2
Replace U12
Replace D3
Date/time
data fails.
Date doesn’t
increment.
Date /time data
doesn’t increment
correctly
Crystal(x2:32.768kHz) is
not oscillating properly.
Check wave form of pin 17 and pin 18 of
U11(frequency:32.768kHz)
Replace crystal(X2)
Buzzer
doesn’t sound
Trouble in buzzer circuit.
When pin 10(P144)of U11 output “H”,
buzzer is driven.
Is Q7 defect?.
Replace the buzzer.
Replace Q7
Drawer is not
opened
Drawer solenoid
doesn’t operate.
Trouble in drawer circuit
When pin 114(P114)of U11 output “H”,
drawer solenoid is driven.
Is Q1 defect?.
Replace Q1
Abnormal
print out
Printed character is
Not desired.
The level of thermister
signal is not stable.
Printer is defect.
Is the signal level of pin 1(U19) stable?
Replace U19
Replace printer
