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http://biz.lgservice.com KIMCHI REFRIGERATOR SERVICE MANUAL CAUTION PLEASE READ CAREFULLY THE SAFETY PRECAUTIONS OF THIS MANUAL BEFORE CHECKING OR OPERATING THE REFRIGERATOR. MODEL : GR-J303T*...
SAFETY INSTRUCTIONS 1. Firstly check that there is electrical leakage in the main body of the product. 2. Perform work always after removing the power plugs in handling with the part where electricity conducts through. 3. Wear a rubber gloves(insulation gloves) for preventing electrical shock accident in case of testing with power on. 4.
1. PRODUCT SPECIFICATIONS 1-1. GR-J303T* MODEL GR-J303TG GR-J303TS ITEMS SPEC SPEC 115V/60Hz 115V/60Hz Rating 300 L 300 L Net Capacity 156 L 156 L Top Compartment Capacity Middle/Bottom 144 L 144 L Compartment 667(W) X 670.4(D) 1775(H)mm 667(W) X 670.4(D) 1775(H)mm...
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ITEMS SPEC SPEC P.T.C P6R8MD P6R8MD Overload Protector 4TM314TFB 4TM314TFB Fan Motor(Top) Ø110 Fan Ø110 Fan Fan Motor(Middle) Ø110 Fan Ø110 Fan Condenser Ø110 Fan Ø110 Fan Cooling Fan Motor Electrical 115 V 140 W 115 V 140 W Defrosting System Heater Middle...
3. MICOM FUNCTION AND EXPLANATIONS OF CIRCUITS 3-1. EXPLANATION OF FUNCTION 3-1-1. DISPLAY PART (1) BEST MODEL(GR-J303TG) (2) BETTER MODEL(GR-J303TS) Cabbage/Radish/ Mul Kimchi Vegetble/ Fruit Light Freezing Frozen Food Chilled Food NOTCH Max Max Temperature 1.0°C -0.5°C -2.0°C 4.5°C 3.5°C 2.5°C -4.0°C -5.0°C -6.0°C -15°C -18°C -21°C -25°C 5.0°C 2.0°C 0.0°C setting 1.
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3-1-2. Food storage/seasoning function (1) When selecting food type and storage temperature 1. Press the “Lock/Unlock” button for more than 2 seconds to “Unlock” the refrigerator. 2. When you press the “Uppper compartment”, ”Store” button in this condition, the storage temperature level changes from “Mid”...
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3-1-3. Rhythm fermenting control pattern diagram 1. The fermenting control pattern varies, depending on the temperature of the Kimchi when it is placed into the storage, the type of Kimchi being made and the degree of the seasoning selected. 2. In the 1st seasoning cycle, if the Kimchi is at room temperature, the cold control operates. 3.
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3-1-4. TEMPERATURE CONTROL AT UPPER, MIDDLE AND LOWER COMPARTMENT (1) Temperature control at upper compartment 1. Turn COMP, upper compartment fan motor depending on temperature of the upper compartment sensor and cool them by opening the 3-way valve to the upper compartment. 2.
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3-1-7. FRONT-C HEATER CONTROL 1. A heater for prevention of dewing is installed on the FRONT-C part between the middle compartment and the lower compartment, and turns on at the time of COMP ON and for 20 minutes after COMP OFF. 2.
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3-1-12. SEQUENTIAL OPERATION OF ELECTRICAL PARTS Electrical parts such as COMP, defrosting heater at the upper & middle compartment, fan motor at the upper & middle compartment, single motor damper and FRONT-C heater sequentially operate as followers for preventing noise and damage of parts occurred by that various parts operate at the same time in input of initial power on and after test closing (including temporary power failure, either): Function...
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3. The product returns to normal operation if failure is released during display of failure code in occurrence of failure (RESET). 4. LEDs other than failure code turn off in occurrence of failure. BEST MODEL (GR-J303TG) BETTER MODEL (GR-J303TS) Failure Display Item (Food LED) Remarks Failures...
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(2) Load Operation in Failure Classification DEFROSTING DEFROSTING UPPER MIDDLE STEPPING SINGLE ITEM HEATER OF HEATER OF 3-WAY FRONT-C COMP COMPARTMENT COMPARTMENT MOTOR MOTOR UPPER MIDDLE VALVE HEATER DAMPER DAMPER COMPARTMENT COMPARTMENT Normal Failure of 15 min Upper compartment 15 min (K1) sensor Failure of 15 min...
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3-1-14. TEST FUNCTION 1. Test function is intended to check function of PCB and the product and find a failure part with failure status. 2. The test S/W exists on the main PCB, and ends the test mode after 2 hours irrespective of the test mode, and then returns to normal status.
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3-2. EXPLANATION OF CIRCUITS 3-2-1. POWER CIRCUIT Power circuits consist of SMPS (Switching Mode Power Supply) power, and the SMPS consists of the rectification part (BD1, CE1) to convert AC voltage to DC voltage, the switching part (IC3) to switch the converted DC voltage, a transformer to transfer energy of the primary side on the switching terminal, secondary side power to supply power to the MICOM and IC and the feed back part (IC4, IC5) to feedback the secondary side voltage to the primary side of transformer in order to maintain it uniformly.
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3-2-4. LOAD/BUZZER DRIVE CRICUIT (1) Load Drive Circuit COMP, UPPER UPPER MIDDLE MIDDLE MIDDLE LOWER SINGLE FRONT-C Type of Load Mechanical DEFROST DEFROST FERMENT FERMENT MOTOR HEATER Area FAN MOTOR HEATER MOTOR HEATER HEATER HEATER DAMPER Measuring Point(IC7) No.10 No.16 No.12 Q1 Collector No.11...
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(2) Buzzer driving circuit (located on display PCB) g Only the buzzer sound for the Lock/Unlock operation is shown in this SVC technical manual. LED MODULE TYPE (INT1) (PWM3/TC3/PDO3) Status Ex) Lock: "Ding-D-Dong" sound Ex) Lock: "Ding-D-Dong" sound Measuring point 45ms 45ms 45ms 45ms 70ms 750ms...
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3-2-6. TEMPERATURE SENSING CIRCUIT (LED:6871JB1400, LCD:6871JB1399) Above circuits consist of the upper sensor, middle sensor, lower sensor for adjusting setup temperature at the upper, middle and lower compartment, the ambient temperature sensor to detect ambient air temperature, the upper defrost sensor and the middle defrost sensor attached to the evaporator at the upper, middle compartment to detect the defrost return temperature.
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3-2-7. TEMPERATURE SENSING CIRCUIT 1.Temperature adjustment at the lower compartment consists of the circuit part for driving the damper, as electronic single motor damper, to open or close the baffle and the reed switch part to detect open/close status of the damper. 2.
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3-2-8. STEPPING MOTOR DAMPER DRIVE CIRCUIT (FOR TEMPERATURE CONTROL AT MIDDLE COMPARTMENT) As for motor drive, the motor rotates since rotation magnetic force is formed at coils wound around each phase of the motor and the stator if outputting “High” “Low” signal as much as the fixed step numbers through the MICOM pin 51 and pin 52 after applying “High”...
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3-2-9. 3-WAY VALVE STEPPING MOTOR DRIVE CIRCUIT (FOR SWITCHING UPPER/MIDDLE/LOWER COMPARTMENT CYCLE) As for motor drive, the motor rotates since rotation magnetic force is formed at coils wound around each phase of the motor and the stator via the IC11 (TD62308AP) as IC for motor drive if outputting “High” “Low” signal as much as the fixed step numbers from the MICOM pin 50, 47 and 48.
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3-2-10. KEEPING TEMPERATURE COMPENSATION AND TOO COLD/ TOO WARM CUT COMPENSATION CIRCUIT (1) Keeping Temperature Compensation Circuit 16.2KF (UPPER COMPARTMENT SENSOR) MIDDLE COMPARTMENT KEEPING TEMPERATURE COMPENSATION LOWER COMPARTMENT KEEPING TEMPERATURE COMPENSATION u This circuit is used for entering the required level of temperature compensation into MICOM to adjust keeping temperature at the upper, middle and lower compartment.
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u Temperature compensation table at the upper compartment is as follows: Modification RCF1:3 K RCF1:2.4 K RCF1:1.8 K RCF1:1.2 K RCF1:620 RCF1: RCF1: RCF1: RCF1: RCF1: RCF1: Division RCF2: RCF2: RCF2: RCF2: RCF2: RCF2: RCF2:1.2 K RCF2:2.4 K RCF2:3 K RCF2:5.1 K RCF2:6.2 K Current...
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(2) Too Cold/Too Warm Cut Compensation Circuit. Upper compartment Upper Middle compartment Lower compartment compartment cut compensation cut compensation cut compensation Middle Lower temperature compartment compartment Too cold Too warm Too cold Too warm Too cold Too warm compensation temperature temperature compensation compensation...
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3-2-11. COMMUNICATION CIRCUIT BETWEEN MAIN PCB AND DISPLAY PCB Following circuits as communication circuits are circuits for changing necessary information between the main MICOM of the main PCB and the MICOM for LED control of the display PCB. DC12V for driving the display PCB, transmit/receive circuits are required. Poor communication occurs where continuing information change between the main MICOM of the main PCB and the MICOM for LED control of the display PCB is not done for more than 30 seconds.
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3-3. SENSOR RESISTANCE CHARACTERISTICS TABLE Measuring Temperature(°C) Upper/Middle/Lower sensors, RT sensor, Upper/Middle defrosting sensors -20 °C 77 K -15 °C 60 K -10 °C 47.3 K -5 °C 38.4 K 0 °C 30 K +5 °C 24.1 K +10 °C 19.5 K +15 °C 15.9 K...
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3-4. PCB PARTS DIAGRAM AND LIST 3-4-1. PWB(PCB) ASSEMBLY, MAIN(LED MODULE TYPE) (1) Parts diagram 6871JB1129 "W" - 27 -...