LG LRTBC1825T Service Manual page 20

7-3 Failure diagnosis method of ice maker
DC power (5V,12V) is
normally output?
Yes
Normally perform
ice-removing and returning to
the level if pressing TEST S/W
for more than 0.5
second?
Yes
Water supply is
normal after the ice-making tray
and returning to the level with the
ice-removing motor?
Yes
Normal
No
Defect of power terminal
• Check DC power (5V,12V)
No
Defect of ice-making sensor
• Check resistance values of
both ends of ice-making sensor
(Pin for PCB CON2 1,2 PIN)
• Ice-making sensor~Defect
between (PIN NO # 4 of IC1)
boards
Defect of ice-making kit
• Resistance values at both
ends of ice-removing motor
(# 7,8 pin of PCB CON2 7,8)
is 18°~22Ω ?
• Drive circuit of ice-removing
motor (IC5 and auxiliary
circuit) is normal?
• HALL IC~Defect between
(PIN NO # 20 of IC1) boards
• Be sure ice-removing and
returning to the level when
pressing the TEST S/W
Defect of ice-making KIT TEST S/W
• Both ends of TEST S/W
(# 3,6 pin of PCB CON2 3,6)
are at open status?
• TEST S/W ~ Defect between
boards (PIN NO #19 of IC1)
No
Defect of water supply
• Water supply valve conduct
current?
• Water supply pump normally
operates?
• Water supply line is normally
connected?
- 20 -
Replacement of
MAIN PCB
Replacement of
ice-making sensor
Replacement of
ice-making kit
Replacement of
MAIN PCB
Replacement of
ice-making kit
Replacement of
water supply valve