LG Gr P227 Ytqa Service Manual

							✽The fan motor at the freezing room does not stop but operates if opening doors of the freezing room or cold storage room
or the home bar during operation of the fan motor at the freezing room.
✽(A), (B), (C) and (D) of door switch for the freezing room or cold storage room are connected to the door open sensing
circuit toward both ends of switch to determine door open at MICOM.
✽Since a door switch of the home bar is connected to door switch (C), (D) of the cold storage room, it senses door opening
if even one of both is opened.
EXPLATION FOR MICOM CIRCUIT 
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P.T.C       ASSEMBLY COMP
Measuring part (IC6) No.16 No.11 No.10 No.15 No.14
StatusON Within 1 V
OFF 12 V
Type of Load COMPFrost Removal
HeaterAC Converting
RelayR-room LAMPHomebar
Heater
 
						

							EXPLATION FOR MICOM CIRCUIT 
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ASSEMBLY
Measuring part (IC6) No.16 No.11 No.12 No.15 No.14
StatusON Within 1 V
OFF 12 V
Type of Load COMPFrost Removal
HeaterAC Converting
RelayR-room LAMPHomebar
Heater
 
						

							2. Dispenser operation circuit
EXPLATION FOR MICOM CIRCUIT 
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							1) Check load driving status 
2) Lever S/W sensing circuit
EXPLATION FOR MICOM CIRCUIT 
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Measuring part
Lever S/WIC1(Micom) No.15 (16)
On(Press)
OFF 5V
0 V(60 Hz) 5 V
Measuring part IC7-No.16 IC7-No.15 IC7-No.14 IC7-No.13 IC7-No.12 IC7-No.11 IC7-No.10
StatusON Within 1 V
OFF 12 V
Type of LoadGEARED
MOTORSOLENOID
CUBEWATER VALVE
ICE WATERPILOT
VA LV ESOLENOID
DISPENSERHOME BAR
HEATER
 
						

							3. Door opening sensing circuit
EXPLATION FOR MICOM CIRCUIT 
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							✽Since door switch sensing switch (A), (B) are a separate switch even if the door switch of the freezing room normally
operates, they may fail to sense door opening in the failure of switch at both ends of (A) and (B) or in failure of the L/wire. 
✽Lamp does at the cold storage room not turn on if the door switch of the cold storage room fails to sense the door open
switch (c ), (d) or the home bar switch.
EXPLATION FOR MICOM CIRCUIT 
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Closing 5 V ( A  -  B ,  C  -  D,  E  -  F  . S/W at both ends are at Off status)
Opening 5 V ( A  -  B ,  C  -  D,  E  -  F  . S/W at both ends are at On status)
Measuring part
IC1 (MICOM) No. 47, 46 Pin
Door of Freezing/Cold Storage Room
CONDITIONS
Bell sounds when button on  Beep sounds when warning
MEASURING dosplay is pressed. door opening.OFF
POINTS
IC1 (No. 48 Pin)5 V
IC1 (No. 51 Pin)0 V
0.05 s
2.63 kz (DING)2.63 kz (BEEP)OFF 2.21 kz (DONG)
0.2 s 0.1 s 0.4 s 0.5 s 0.5 s
5 V
0 V
5 V
0 V5 V
0 V
5 V
0 V
 
						

							1-5. Temperature sensing circuit
EXPLATION FOR MICOM CIRCUIT 
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							The above circuits are circuits attached to freezing room sensor or cold storage room sensor for adjusting setting
temperature at the freezing room and cold storage room, ice-making sensor for sensing water temperature in ice-making, or
an evaporator for sensing temperature of a frost removal sensor necessary for frost removal. Short or open status of every
temperature sensor is as follows:
SENSOR CHECK POINTNORMAL(-30 °C ~ 50 °C) IN SHORT IN OPEN
Freezing sensor POINT  A  Voltage
Frost removal sensor POINT  B  Voltage
Cold storage sensor 1 POINT  C  Voltage
0.5 V~4.5 V 0 V 5 V
Cold storage sensor 2 POINT  D  Voltage
Ice making sensor POINT  E  Voltage
Room temperature sensor POINT  F  Voltage
EXPLATION FOR MICOM CIRCUIT 
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							EXPLATION FOR MICOM CIRCUIT 
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E
A
B
C
D
 
						

							The above circuits are circuits attached to freezing room sensor or cold storage room sensor for adjusting setting
temperature at the freezing room and cold storage room, ice-making sensor for sensing water temperature in ice-making, or
an evaporator for sensing temperature of a frost removal sensor necessary for frost removal. Short or open status of every
temperature sensor is as follows:

A
E
B
D
C
SENSOR CHECK POINTNORMAL(-30 °C ~ 50 °C) IN SHORT IN OPEN
Freezing sensor POINT  A  Voltage
Frost removal sensor POINT  B  Voltage
Cold storage sensor 1 POINT  C  Voltage 0.5 V~4.5 V 0 V 5 V
Cold storage sensor 2 POINT  D  Voltage
Room temperature sensor POINT  E  Voltage
EXPLATION FOR MICOM CIRCUIT 
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