LG Gr P227 Ytqa Service Manual

							3. Ice Maker Troubleshooting
* Troubleshooting:it is possible to confirm by  pressing freezer   and refrigerator temperature   control buttons  for more
than 1 second. (ice maker is normal if all leds are on): refer to trouble diagnposis function in MICOM
function 2-8 (page 18)

ICE MAKER AND DISPENSER WORKING PRINCIPLES AND REPAIR
- 71 -
No
Yes
Yes
Yes
No
No No
No
Yes
YesIs DC Power (5V and 12V) 
output normal?Failed DC Power
• Check DC power (5V, 12V).Change main PWB
Is cube ice led off during
troubleshooting check?Failed ice making sensor
• Check the resistance of 
both ends (1,2) of ice making 
sensor of CON8. 
• Defects between ice making 
sensor and board 
(Pin No.  60 of IC1)Replace Ice making
Sensor
Is Crushed Ice LED off during
troubleshooting check?Failed Ice Maker Unit
• Is the resistance of both ends 
9,10 of ice ejection motor of 
CON8 between 18 and 22Ω?
• Is ice ejection motor drive circuit
(IC11 and peripheral circuits)
normal?
• Defects between Hall IC and 
Board (Pin No. 42 of IC1).
• Confirm ice ejection and level
return when pressing 
test switch.Replace Ice Maker Unit
Replace Main PWB
Are ice
ejection and level return 
normal when test switch is
pressed for more than 0.5 second?
Does the bell 
sound once?
Failed ice maker unit test switch
• Are both ends 5,6 of CON8 
test switch  open?
• Defects between test switch
and board (Pin  No. 40 of IC1).
• Are  both ends (3,4) of CON8
ice maker  stop switch  short?Replace Ice maker Unit
Replace water 
supply valve
• Is power applied to water 
supply valve?
• Does the water supply 
valve work normally?
• Is the water supply line 
normally connected?Poor water supply Is water suppy normal
after Ice ejection and level return
by ice ejection motor?
Normal
 
						

							- 72 - 
ICE MAKER AND DISPENSER WORKING PRINCIPLES AND REPAIR
No
Yes
Yes
Yes
No
No No
No
Yes
YesIs DC Power (5V and 12V) 
output normal?Failed DC Power
• Check DC power (5V, 12V).Change main PWB
Is cube ice led off during
troubleshooting check?Failed ice making sensor
• Check the resistance of 
both ends (1,2) of ice making 
sensor of CON8. 
• Defects between ice making 
sensor and board 
(Pin No.  59 of IC1)Replace Ice making
Sensor
Is Crushed Ice LED off during
troubleshooting check?Failed Ice Maker Unit
• Is the resistance of both ends 
9,10 of ice ejection motor of 
CON8 between 18 and 22Ω?
• Is ice ejection motor drive circuit
(IC11 and peripheral circuits)
normal?
• Defects between Hall IC and 
Board (Pin No. 46 of IC1).
• Confirm ice ejection and level
return when pressing 
test switch.Replace Ice Maker Unit
Replace Main PWB
Are ice
ejection and level return 
normal when test switch is
pressed for more than 0.5 second?
Does the bell 
sound once?
Failed ice maker unit test switch
• Are both ends 5,6 of CON8 
test switch  open?
• Defects between test switch
and board (Pin  No. 42 of IC1).
• Are  both ends (3,4) of CON8
ice maker  stop switch  short?Replace Ice maker Unit
Replace water 
supply valve
• Is power applied to water 
supply valve?
• Does the water supply 
valve work normally?
• Is the water supply line 
normally connected?Poor water supply Is water suppy normal
after Ice ejection and level return
by ice ejection motor?
Normal
 
						

							CIRCUIT
- 73 -

 
						

							CIRCUIT
- 74 -

 
						

							1. TROUBLE SHOOTING
TROUBLE DIAGNOSIS
- 75 -
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
1. Faulty start
1) No power on outlet.
2) No power on cord.
3) Shorted  start circuit.
4) During defrost.* Measuring instrument :
Multi tester
Check the  voltage.
If the voltage is within ±85%
of the rated voltage, it  is OK.
 Check the terminal
movement.
 
Check both terminals of
power cord.
Power conducts : OK.
No power conducts : NG
 Check both terminals of
O.L.P.
If power conducts : OK.
If not : NG.
 Check the resistance of both
terminals.
At normal temperature 6 :
OK.
If disconnected : ∞.
Bad connection between adapter and outlet. (faulty adapter)
The  Inner diameter of adapter.
The distance between holes.
The distance between terminals.
The thickness of terminal.
Bad connection between plug  and adapter (faulty plug).
The distance between pins.
Pin outer diameter.
No power on
power cord.
O.L.P is off.
No electric power on compressor. - Faulty compressor.
Faulty PTC.Disconnected copper wire.
Internal electrical short.
Faulty terminal contact.
Disconnected. 
Capacity of O.L.P is small.
Characteristics of O.L.P is bad.
Bad connection.
Power is 
disconnected.Inner Ni-Cr wire blows out.
Bad internal connection.
Faulty terminal caulking (Cu wire is cut).
Bad soldering.Weak connection.
Short inserted cord length.
Worn out tool blade.Loose contact.
- Large distance between
male terminal.
- Thin female terminal.
Terminal disconnected.
Bad sleeve assembly.Power cord is disconnected.
Faulty soldering.
Start automatic defrost.
Cycle was set at defrost when the refrigerator
was produced.
Power does not conduct. - Damage.
Bad characteristics. - Initial resistance is big.
Bad connection with
compressor.
Bad terminal connection.Too loose.
Assembly is not possible.
 
						

							TROUBLE DIAGNOSIS
- 76 -
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
2. No cooling.
2) Refrigeration system is clogged.Check the clogged
evaporator by heating (as
soon as the cracking sound
begins, the evaporator start
freezing)
 The evaporator does not cool
from the beginnig (no evidece
of misture  attached).
The evaporator is the same
as before even heat is
applied.
Moisture
clogged.
No electric
power on
therm-
ostat.
Weld joint
clogged.
Drier cloggeing.
Foreign material clogging.Residual moisture
in the evaporator.
Residual moisture.
Insufficient drier
capacity.
Residual moisture 
in pipes.
Moisture penetration - Leave it in the air. - Moisture penetration.
into the refrigeration oil.Caps are missed.
Air blowing.During transportation.
During work.
Not performed.
Performed.
Too short time.
Low air pressure.
Less dry air. Air Blowing.
Leave it in the air.
Caps are missed.
Short pipe insert.
Pipe gaps.
Too much solder.Too large.
Damaged pipes.
Not dried in the compressor.
Elapsed more than 6 months after drying
Caps are missed.
No pressure when it is open.
During rest time.
After work.
Compressor cap is disconnected.
Foreign materials are in the pipe.
Not performed.
Too short.
Impossible moisture
confirmation.
Low air pressure.
Dry drier - Drier temperature.
Leave it in the air.
The capillary tube inserted depth. - Too much.
Capillary tube melts. - Over heat.
Clogged with foreign materials.
Reduced cross section by cutting. - Squeezed.Desiccant powder.
Weld oxides.
Drier angle.
Check on package
condition.
Good storage after
finishing.
 
						

							TROUBLE DIAGNOSIS
- 77 -
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
3. Refrigeration 
is weak.
Heater 
Sheath
1) Refrigerant Partly leaked.
2) Poor defrosting capacity.
Drain path (pipe) clogged.
Defrost heater does not 
generate heat.
Weld joint leak.
Parts leak.
Inject P/U into drain hose.
Foreign materials
penetration.
Cap drain is not disconnected.Inject through the
hole.
Seal with drain.
P/U lump input.
Screw input.
Other foreign materials
input.
Parts 
disconnected.Wire is cut.
- Lead wire.
- Heating wire.
- Contact point
between heating and
electric wire.
Dent by fine evaporator.
Heating wire is corroded
- Water penetration.
Bad terminal connection.
Check visually.
Check terminal 
Conduction: OK.
No conduction: NG.
If wire is not cut, refer to
resistance.
P=Power
V=Voltage
R=Resistance
V
2P=  —   
R
V
2R=  —   
P
 
						

							- 78 -
TROUBLE DIAGNOSIS
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
3. Refrigeration 
is weak.
3) Cooling air leak.
4) No cooling air circulation.
Residual
frost.
No automatic defrosting.
Defrost does not return.
Bad gasket adhestion
Door sag.
Faulty fan motor.Weak heat from heater.
Too short defrosting time. Defrost Sensor.
- Faulty characteristics.
Seat-D(missing, location. thickness).
Structural fault. Gasket gap.
Air inflow through the fan motor.
Bad insulation of case door.Sheath Heater - rated.
Heater plate - rated.
Gap.
Bad attachment.
Contraction.
Bad adhesion.
Weak binding force at hinge.
Fan motor.
Door switch.Self locked.
Wire is cut.
Bad terminal contact.
Contact distance.
Button pressure.
Melted contact.
Contact.
Poor door
attachment.
Door liner
(dimension).
Contraction inner
liner.
Misalignment.
Bad terminal
connection.
P/U liquid leak. Faults.
Refrigerator and freezer switch reversed.
Button is not  pressed.
Check the fan motor
conduction: OK.
No conduction: NG.
 
						

							TROUBLE DIAGNOSIS
- 79 -
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
3. Refrigeration 
is weak.
4) No cooling air circulation.
5) Compressor capacity.
6) Refrigerant 
too much or too little.
7) Continuous operation
-  No contact of temperature controller. - Foreign materials.
8) Damper opens continuously.
Foreign materials 
jammed.
Failed sensor.  -  Position of sensor.
Characteristics 
of damper.
9) Food storing place. - Near the outlet of cooling air.
Faulty fan motor.
Small cooling air
discharge.Fan is 
constrained.
Insufficient
motor RPM
Faulty fan.
Shorud.        Bent.
Ice and foreign materials on rotating parts.Fan shroud contact. - Clearance.
Damping evaporator contact.
Accumulated residual frost.
Fan misuse.
Bad shape.
Loose connection. - Not tightly connected.
Insert depth.
Rating misuse.
Small capacity.
Low valtage.
Malfunction of charging cylinder.
Wrong setting of refrigerant.
Insufficient compressor. - Faulty compressor.Fan overload. - Fan misuse.
Bad low termperature RPM characteristics.
Rated power misuse.
Low voltage.
P/U liquid dump.
EPS water sediment.
Screw.
Bad characteristics of its own temperatue.
Parts misuse.
Charge of temperature - Impact.
characteristics.
Check visually after
disassembly.
Check visually after
disassembly.
 
						

							TROUBLE DIAGNOSIS
- 80 -
CLAIMS. CAUSES AND CHECK POINTS. HOW TO CHECK
4. Warm
refrigerator
compartment
temperature.
5. No automatic
operation.
(faulty 
contacts.)
6. Dew and 
ice formation.
1) Colgged cooling path.
2) Food storate.
1) Faulty temperature sensor in freezer or refrigerator compartment.
2) Refrigeration load is too much.
3) Poor insulation.
4) Bad radiation.
5) Refrigerant leak.
6) Inadequate of refrigerant.
7) Weak compressor discharging power.
8) Fan does not work.
9) Button is positioned at strong.
1) Ice in freeezer compartment.
2) Condensation in the refrigerator compartment.
3) Condensation on liner foam.
P/U liquid leak.
Foreign materials. –– P/U dump liquid.
Faulty contact.
Faulty temperature characteristics.
External air inflow. –– Rubber motor assembly direction(reverse).
Door opens 
but not closes.
Gap around gasket. –– Contraction, distortion, loose, door twisted, corner not
fully inserted.
Food vapor.  –– Storing hot food. –– Unsealed food.
Door opens
but not closes.
Gasket gap.
Cool air leak
and transmitted.
High ambient temperature.
Space is secluded.
Different rating.
Small capacity. Store hot food.
Store too much at once.
Door open.
Packages block air flow.
Food.
Frequent opening and closing.
Cool air leak.
Poor door close. – Partly opens.Too much food.
Hot food.
Weak door closing power.
Stopper malfunction.
Door sag.
Food hinders door closing.
Insufficient closing.
Door sag.
Food hinders door closing.
Toop table part.
Out plate R/L part. Not fully filled.
Flange gap. –– Not sealed.
Gasket gap.
Inspect parts measurements
and check visually.