LG GR-L247ER Parts List And Instructions Manual page 65

2-9. Micom '_1
Problems Causes Remarks
i
co
Bad PCB
electric power.
Symptom
All display
LEDS are off.
Abnormal
display LED
operation
Bad connection
between Main PCB
and display circuit.
Defective PCB trans.
DefectivePCB electric
circuitparts,
Bad connection
between Main PCB
and display circuit,
Defective LED
module.
Bad connector
connection from mai£_
I PCB to display PCB,
PCB Trans winding is
cut.
PCB Trans temperature
fuse is burnt out,
Defective regulator IC
7812, 7805).
PCB electric terminal
fuse is burnt out.
STR Parts are
damaged.
Lead Wire connecting
main PCB and display
PCB is cut or connector
terminal connection is
bad.
Defective LED.
Checks
Visual check on connector
connection.
Check resistance of PCB Trans
! input and output terminals with
a tester. (If resistance is infinity,
trans winding is cut),
Check voltage at input/output
terminals.
Check fuse in PCB electric
terminal with a tester.
Check if STR No. 2 and 3 pins
are cut when power is off.
Check Lead Wire terminals
connecting Main PCB and
display PCB with a tester.
Check if all LEDs are on when
Main PCB Test switch is
pressed (or when both freezer
key and power freezer key are
pressed at the same time for
more than one second.)
Measures
Reconnect
connec_r.
Replace PCB Trans
or PCB.
Replace regulator.
Replace PCB fuse.
Replace parts.
Reconnect Lead
Wiraand direGly
connect defective
contact tarminalto
Lead Wire.
Replace display
PCB.
Applioableto
model without
dispenser.
Refer to electdc
circuit in circuit
explanation.
App]icable to
model with
dispenser.
Refer to display
circuit in circuit
explanation.
o