40
Diagnostics
3) Without sound of buzzer operation
Does it sound
‘
Ding-Dong
’
if you press a button
on front panel?
Start
Main PCB is normal; buzzer normal.
Check the panel PCB with the
reference of ‘how to check panel
display’.
Buzzer is broken – replace it.
Does it make a sound of ‘door-open’ alarm
when you are opening the door of freezer or fridge
more than 2 min?
Is the bent or go-out of the buzzer
in the main PCB?
The main PCB and buzzer are normal
YES
YES
NO
NO
YES
NO
NO
Replace the main PCB.
(failure of MICOM)
Are signals coming
out of MICOM No. 21 in a 1-sec cycle
after the Forced operation?
Is signal of Q801
Base ouputted with 1 sec. intervals
in the condition above?
Did lead of a
component fall on the vibration plate
of buzzer?
NO
Check the state of pattern connection
between MICOM No.21 and Q801.
(Check Open/Short)
NO
Poor buzzer is broken down or
replace the buzzer.
YES
YES
YES
Refer the description of
Test function in the manual
for the Forced operation.
