2-9. Micom
TROUBLE DIAGNOSIS
- 117 -
Problems Symptom Causes Checks Measures Remarks
Bad PCB  All display  Bad connection  Bad connector Visual check on connector  Reconnect 
electric power. LEDS are off. between Main PCB  connection from main  connection. connector.
and display circuit. PCB to display PCB.
Defective PCB trans. PCB Trans winding is  Check resistance of PCB Trans Replace PCB Trans Applicable to 
cut. input and output terminals with or PCB. model without
PCB Trans temperature a tester. (If resistance is infinity, dispenser.
fuse is burnt out. trans winding is cut).
DefectivePCB electric Defective regulator IC Check voltage at input/output Replace regulator. Refer to electric
circuit parts. (7812, 7805). terminals. circuit in circuit 
explanation.
PCB electric terminal Check fuse in PCB electric  Replace PCB fuse.
fuse is burnt out. terminal with a tester.
STR Parts are  Check if STR No. 2 and 3 pins Replace parts. Applicable to 
damaged. are cut when power is off. model with
dispenser.
Abnormal  Bad connection  Lead Wire connecting  Check Lead Wire terminals  Reconnect Lead  
display LED between Main PCB  main PCB and display connecting Main PCB and  Wire and directly 
operation and display circuit. PCB is cut or connector display PCB with a tester. connect defective 
terminal connection is contact terminal to 
bad. Lead Wire.
Defective LED  Defective LED. Check if all LEDs are on when  Replace display  Refer to display
module. Main PCB Test switch is  PCB. circuit in circuit
pressed (or when both freezer explanation.
key and power freezer key are  
pressed at the same time for  
more than one second.)