LG LFX25978 Series Service Manual Download

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12-6-2 SEALED SYSTEM DIAGNOSIS

“Not Cooling” Complaint

All components operating, No airflow problems, Not frosted up as a defrost

problem

problem has been isolated to sealed system area

Frost

Pattern?

Partial

Equalization

Test

Very Slow

None

Equalization

Test

Very Fast

Fast

Very Fast

Inefficient

Compressor

Partial

Restriction

Complete

Restriction

Condenser

Temperature

Cap Tube

Sound

Yes

Air/Low Side

Leak

Loss of Change

Very Slow

Faint

Hotter than Normal

None to Weak

Room Temperature

Compressor Not

Pumping

Trace of Oil

Undercharge

(The equalization test is trying to restart a compressor using a start kit after it has been operating.)

Leak

Summary of Contents for LFX25978 Series

Page 1: ...CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL MODEL LFX28978 LFX25978 COLOR STAINLESS ST SMOOTH BLACK SB SUPER WHITE SW REFRIGERATOR SERVICE MANUAL ...

Page 2: ...HOD 16 FAN AND FAN MOTOR DISASSEMBLY METHOD 16 DRAWER REMOVAL 17 4 ADJUSTMENT 18 5 CIRCUIT DIAGRAM 19 20 6 TROUBLESHOOTING 21 7 PCB PICTURE 22 24 8 Troubleshooting With Error Display 25 33 9 Troubleshooting Without Error Display 34 42 10 Reference 43 46 11 COMPONENT TESTING INFORMATION 47 55 12 COMPRESSOR TROUBLESHOOTING 56 68 13 ICEMAKER OPEARTING AND TROUBLE SHOOTING METHOD 69 72 14 DESCRIPTION ...

Page 3: ...BLE TRAY COMPRESSOR EVAPORATOR CONDENSER REFRIGERANT LUBRICATING OIL DEFROSTING DEVICE ITEMS Clear Drawer Type Linear Fin Tube Type Spiral Condenser R 134a 140 g ISO10 280 ml SHEATH HEATER LED Module 24 Bulb Lamp SPECIFICATIONS LAMP REFRIGERATOR FREEZER DIMENSIONS Depth w Handles Depth w o Handles Depth w o Door Depth Total with Door Open Height to Top of Case Height to Top of Door Hinge Width Wid...

Page 4: ...OMPRESSOR EVAPORATOR CONDENSER REFRIGERANT LUBRICATING OIL DEFROSTING DEVICE ITEMS Clear Drawer Type Linear Fin Tube Type Spiral Condenser R 134a 125 g ISO10 280 ml SHEATH HEATER LED Module 24 Bulb Lamp SPECIFICATIONS LAMP REFRIGERATOR FREEZER DIMENSIONS Depth w Handles Depth w o Handles Depth w o Door Depth Total with Door Open Height to Top of Case Height to Top of Door Hinge Width Width door op...

Page 5: ...allow flexibility for storage needs GALLON STORAGE BINS 2 Three interchangeable bins can be arranged to suit your storage needs REMOVABLE ICE STORAGE BIN 3 The ice storage bin can be removed to fill ice buckets coolers or pitchers LED INTERIOR LAMPS 4 Refrigerator interior is lit by the LED array CAN STORAGE BIN 5 FIXED DOOR BIN 6 ...

Page 6: ... pin and remove door 8 Place the door with the insides facing up on a not scratch surface CAUTION When lifting hinge free from the latch be careful that door does not fall forward Right Door FIG 3 1 Open the door remove 1 screw on the top of the hinge cover Loosen top hinge cover screw 1 Lift up cover 2 2 Disconnect door switch wire harness and remove the cover 3 Rotate hinge lever 3 clockwise Lif...

Page 7: ...n up carefully 3 Disconnect wire harness Door Gasket Replacement 1 Insert gasket into channel Press gasket into channels on the four remaining sides of door 2 Insert mullion into the channel Insert the cover assembly into bracket door Mullion Replacement 1 Connect wire harness 3 Assemble 2 screws Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 ...

Page 8: ...fter cutting the Tie Wrap Figure 13 Figure 12 Figure 13 GRILLE ASSEMBLY DEFROST CONTROL ASSEMBLY 3 3 Door Alignment If the space between the door are uneven follow the instructions to align them Remove the Base Grillie Turn the leveling legs counter clock wise to raise or clock wise to lower the height of the front of the refrigerator by using flat blade screw driver or 11 32 wrench Use the wrench...

Page 9: ... lead wire on the bottom position Figure 19 Figure 14 Figure 15 3 6 LAMP Unplug or disconnect power at the circuit breaker If necessary remove top shelf or shelves 1 Release 2 screws 2 Hold both ends and pull down to remove 3 6 1 Refrigerator Compartment Lamp Figure 16 4 Use a flat tool as shown below to remove the lamp cover Figure 17 5 To remove the LED assembly pull apart the cover Cover lamp C...

Page 10: ... hook 3 Push and pull on the tab to remove CAUTION When replacing the dispenser cover make sure the lead wire does NOT come off and the water line is not pinched by the dispenser Case PCB Button Lever Display PCB Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 30 Figure 28 Case PCB Display PCB Figure 29 Figure 28 2 Use these 2 holes to pull out the bottom 3 If nozzle is interfer...

Page 11: ...Door with the other hand 3 12 WATER BUTTON ASSMEBLY 1 Remove screws 2 Grasp the Button assembly and lift Button Lever hinge 3 14 ICEMAKER REPLACEMENT 1 Remove 4 screws as shown 2 Grasp the bottom of motor cover assembly and pull slowly 3 Disconnect wire harness from wall of compartment In door motor Figure 31 Figure 32 Figure 35 Figure 33 Figure 34 ...

Page 12: ...osition 2 Unscrew 3 screws to disassemble the motor 4 Insert 2 screws 5 Push housing aside 3 15 SUB PWB FOR WORKING DISPENSER 1 Disconnect the wire harness 2 Remove 1 screw from PWB and replace with new PWB CAUTION Make sure that the motor housing is taped to the mold if not positioned correctly the cover will not fit properly Figure 36 Figure 37 Figure 38 Figure 43 Figure 42 Figure 41 Figure 40 F...

Page 13: ... handles as shown 2 Tilt and lift slightly as shown 3 18 HOW TO INSERT A ICE BIN 1 Insert the Ice Bin slightly tilting to avoid touching the Icemaker Especially Ice Detecting Sensor 3 Remove ice bin slowly Figure 44 Figure 45 Figure 46 Figure 47 ...

Page 14: ...ne by lifting clear of the rail support Fully extend both rails Step 5 First Remove the gear from the left side first by releasing the tab behind the gear place a screwdriver between the gear and the tab and pull up on the gear Second Remove the center rail Third Remove the gear from the right side by following the same steps for the left side NOTE THIS TAB MUST BE PUSHED IN TO RELEASE THE GEAR Fi...

Page 15: ...ear and insert the gear into the clip Step 4 The rail system will align itself by pushing the rails all the way into the freezer section Pull the rails back out to full extension Step 5 Reinstall the freezer door by inserting the rail tabs into the guide rail Step 6 Reinstall 2 screws into the guide rail one on each side Step 7 Reinstall the lower basket and close the freezer door Figure 53 Figure...

Page 16: ...ollet to separate the tube from the connector Note there maybe some water in the line Mechanical Cover Housing MOTOR COVER 2 Separate the Fan Assembly and Motor turn counter clockwise to remove from the motor shaft FAN ASSEMBLY MOTOR Assemble in reverse order Taking care to avoid 1 Do not to bend the tube during assembly 2 Press the Water Dispenser button letting water pour out this checks for any...

Page 17: ...7 3 22 Drawer Removal Fully extend the drawer and lift from the front pulling straight out To install the drawer back into the frame tilt the front sightly and pushingt back into place Figure 66 Figure 67 ...

Page 18: ...For every 416 7us check whether FO signal is LOW The trip occurs if it is found three times during the five periods 83ms 4 ADJUSTMENT 4 1 1 Role 4 1 COMPRESSOR The compressor intakes low temperature and low pressure gas from the evaporator of the refrigerator and compresses this gas to high temperature and high pressure gas It then delivers the gas to the condenser 4 1 2 Note for Usage 1 Be carefu...

Page 19: ... 19 5 CIRCUIT DIAGRAM LFX28978 ...

Page 20: ... 20 LFX25978 ...

Page 21: ... maker kit defect Er It Other Electric system error such as moter gear Hall IC operation circuit within I M kit When the ice does not drop even when the I M Test S W is pressed 9 Flow Meter Sensor Defect Er gF Error of flow meter or water input or low water pressure Error of flow meter or water input or low water pressure or flow meter connection 11 Abnormality of BLDC FAN Motor for Ice Making Er ...

Page 22: ... 22 7 PCB PICTURE 7 1 Main PCB P No MFG EBR65002710 2010 12 EBR65640204 2010 12 Picture CON1 CON2 CON3 CON8 CON6 CON5 CON4 CON10 CON203 CON201 CON2 LFX28978 ...

Page 23: ... 23 P No MFG EBR65002714 2010 12 EBR65640204 2010 12 Picture CON1 CON2 CON3 CON8 CON6 CON5 CON4 CON10 LFX25978 CON203 CON201 CON2 ...

Page 24: ... 24 7 2 Display PCB Sub PCB P No Display PCB EBR65749301 2010 02 Sub PCB EBR60070707 2010 02 Picture CON2 CON103 CON102 CON101 ...

Page 25: ...Result SVC Action 8 1 Freezer Sensor Error Er FS No 1 2 Checking flow Check for a loose connection Check the Blue White to Blue White Result SVC Action CON6 Temperature table 1 1 To 2 22 F 30 C 13 F 25 C 4 F 20 C 5 F 15 C 14 F 10 C 23 F 5 C 32 F 0 C Result 40 30 23 17 13 10 8 The sensor is sensing the temperature For example 23 indicates 4 F ...

Page 26: ...t SVC Action 8 2 Refrigerator Sensor Error Er rS No 1 2 Checking flow Check for a loose connection Check the White to White Result SVC Action Temperature table 2 1 To 2 23 F 5 C 32 F 0 C 41 F 5 C 50 F 10 C 59 F 15 C Result 38 30 24 19 5 16 The sensor is sensing the temperature For example 30 indicates 32 F CON6 ...

Page 27: ... Table 1 Result SVC Action No 1 2 Checking flow Check for a loose connection Check the Blue to Blue Result SVC Action Temperature table 1 1 To 2 22 F 30 C 13 F 25 C 4 F 20 C 5 F 15 C 14 F 10 C 23 F 5 C 32 F 0 C Result 40 30 23 17 13 10 8 The sensor is sensing the temperature For example 23 indicates 4 F CON101 CON101 Display ...

Page 28: ...st Sensor Error Er dS No 1 2 Checking flow Check for a loose connection Check the Orange to Orange Result SVC Action Check the Brown to Brown Temperature table 3 1 To 2 22 F 30 C 13 F 25 C 4 F 20 C 5 F 15 C 14 F 10 C 23 F 5 C 32 F 0 C Result 40 30 23 17 13 10 8 The sensor is sensing the temperature For example 23 indicates 4 F CON6 ...

Page 29: ... flow Check the Door gasket Check the Defrost control part 3 Input Test 3 Mode Push the button 3 times 4 Check the Blue to Orange Result SVC Action Fuse M Def Heater Def Sensor 5 Release the test mode Push the button 1 times Normal CON3 CON3 Result 112 116 V 0 V SVC Action Go to the 5 Replace Main PCB 6 Check the Blue to Orange Result 0 V 112 116 V SVC Action Explain to customer Replace Main PCB ...

Page 30: ...le an error code is displayed the fan is not working 3 Check the Fan motor Rotate fan using your hand If it is stuck change the motor Cause of ice or rust inside of motor 4 Check the Fan motor voltage Result SVC Action Below 12 V 0 or 5 V 1 2 2 3 Change the PCB Change the motor Point Result SVC Action CON4 2 Status No windy Windy SVC Action Go to 3 Go to 4 3 1 ...

Page 31: ...the PCB short Tip To prevent ice from shorting the connector a new connector was developed Make sure to order the new one 4 Check the Fan motor Frozen Lock ect Result SVC Action 4 Check the Fan motor voltage Below 12 V 0 or 5 V 1 2 2 3 Change the PCB Change the motor Result SVC Action Duct Asm Connector 407A 5209JA 1044A 5209JA 1044A Part Name Old P No New P No No Status No windy Windy SVC Action ...

Page 32: ...le an error code is displayed the fan is not working 3 Check the Fan motor and surrounding Rotate fan using your hand If it is stuck change the motor Result SVC Action 4 Check the Fan motor voltage Below 12 V 0 or 5 V 1 2 2 3 Change the PCB Change the motor Result SVC Action Status No windy Windy SVC Action Check motor Go to the 4 CON4 2 3 1 ...

Page 33: ... CON5 6 Check the White Red to White Black CON101 Display CON101 3 Check the Orange to White Red Result 0 V or 5 V Other SVC Action Change the Display PCB Go to the 4 4 Check the White Black to White Red Result 0 V or 5 V Other SVC Action Change the Main PCB Go to the 5 Result 0 V or 5 V Other SVC Action Change the Display PCB Go to the 6 Result 0 V or 5 V Other SVC Action Change the Main PCB Expl...

Page 34: ...ck the resistance value CON1 CON3 Ice Maker Geared Motor Dispenser Motor 2 1 3 4 Pushing Not pushing 112 115 V Other 0 2 V Other Go to the 3 Change PCB Go to the 3 Change PCB Lever s w Result SVC Action Pushing Not pushing 9 12 V Other 0 2 V Other Go to the 4 Change PCB Go to the 4 Change PCB Lever s w Result SVC Action 1 to 2 3 to 4 31 1 42 1 Other 9 9 12 1 Other It s normal Replace Geared Motor ...

Page 35: ... Pushing Not pushing 112 115 V Other 0 2 V Other Go to the 3 Change PCB Go to the 3 Change PCB Lever s w Result SVC Action Pushing Not pushing 9 12 V Other 0 2 V Other Go to the 4 Change PCB Go to the 4 Change PCB Lever s w Result SVC Action 1 to 2 3 to 4 31 1 42 1 Other 9 9 12 1 Other It s normal Replace Geared Motor It s normal Replace Dispenser Motor Point Result SVC Action CON2 CON1 CON3 Ice M...

Page 36: ...e Machine Room Water Valve In door Pushing Not pushing 112 115 V Other 0 2 V Other Go to the 3 Change PCB Go to the 3 Change PCB Lever s w Result SVC Action Pushing Not pushing 112 115 V Other 0 2 V Other Go to the 4 Change PCB Go to the 4 Change PCB Lever s w Result SVC Action 1 to 2 3 to 4 360 420 Other 360 420 Other It s normal Replace Water Valve It s normal Replace Water Valve Point Result SV...

Page 37: ...ite to White Red 4 Check the Red to Black Closed Open 0 2 V Other 115 V Other It s normal Change the Door S W Change the F Lamp Change the PCB Status Result SVC Action Closed Open 5 V Other 0 V Other Go to the 4 Change door S W Go to the 4 Change door S W Status Result SVC Action Normal Push S W 0 not Infinity Go to the 3 Change door S W Go to the 3 Change door S W Status Result SVC Action CON5 CO...

Page 38: ...ed to Blue Closed Open 0 2 V Other 12 V Other It s normal Change the Door S W It s normal Change the LED Lamp Status Result SVC Action Normal Push S W 0 not Infinity Other Go to the 3 Change door S W Go to the 3 Change door S W Status Result SVC Action Normal 12 V Other Go to the 4 Change the PCB Status Result SVC Action Normal 12 V Other Go to the 5 Change the LED Lamp Status Result SVC Action 5 ...

Page 39: ...w The sensor is determined by the temperature For example 30 indicates 32 F Result SVC Action Temperature 23 F 5 C 32 F 0 C 41 F 5 C 50 F 10 C 59 F 15 C Result 38 30 24 19 5 16 Status Blowing Not blowing SVC Action Go to the 4 Check the R Fan motor Check the damper Go to the 6 4 Check the air temperature Cold or not Status Cold Not cold SVC Action Go to 5 Check the Compressor And sealed system CON...

Page 40: ...an motor voltage 1 3 2 4 Open Closed Not working 1 Mode 2 Mode 1 2 mode Damper is normal Go to 6 Change the damper Test Mode Damper State SVC Action 1 to 2 3 to 4 270 330 Other 270 330 Other It s normal Change damper It s normal Change damper Point Result SVC Action Below 12 V 0 or 5 V 1 2 2 3 Change the PCB Change the motor Point Result SVC Action Sticky Not Sticky Motor Change the motor Go to 7 ...

Page 41: ...he air flow The sensor is determined by the temperature For example 23 indicates 4 F Result SVC Action Status Blowing Not blowing SVC Action Go to the 4 Check the F Fan motor 4 Check the air temperature Cold or not Status Cold Not cold SVC Action Check the Compressor And sealed system 1 To 2 22 F 30 C 13 F 25 C 4 F 20 C 5 F 15 C 14 F 10 C 23 F 5 C 32 F 0 C Result 40 30 23 17 13 10 8 CON6 ...

Page 42: ...he refrigerator door and Check the air flow The sensor is determined by the temperature For example 30 indicates 32 F Result SVC Action Temperature 23 F 5 C 32 F 0 C 41 F 5 C 50 F 10 C 59 F 15 C Result 38 30 24 19 5 16 Status Blowing Not blowing SVC Action Go to the 4 Check the R Fan Check the damper Go to the 5 4 Input Test 2 Mode and check the air flow Push the button 1 time 5 Check the damper r...

Page 43: ...g TPA 1 How to enter the TEST MODE Push the test button on the Main PCB to enter the TEST MODE 2 How to remove Terminal Position Assurance TPA 1 time Comp Damper All FAN on Everything is displayed 2 times Damper closed 22 22 displayed 3 times Forced defrost mode 33 33 displayed Main PWB AC TPA DC TPA ...

Page 44: ...F 5 C 32 F 0 C 41 F 5 C 50 F 10 C 59 F 15 C 68 F 20 C 77 F 25 C 86 F 30 C 95 F 35 C 104 F 40 C RESISTANCE 73 29 53 63 39 66 29 62 22 33 16 99 13 05 10 10 7 88 6 19 4 91 3 91 3 14 2 54 2 07 1 69 1 39 VOLTAGE 4 09 V 3 84 V 3 55 V 3 23 V 2 89 V 2 56 V 2 23 V 1 92 V 1 63 V 1 38 V 1 16 V 0 97 V 0 81 V 0 67 V 0 56 V 0 47 V 0 39 V ...

Page 45: ... C 32 F 0 C 41 F 5 C 50 F 10 C 59 F 15 C 68 F 20 C 77 F 25 C 86 F 30 C 95 F 35 C 104 F 40 C RESISTANCE 225 1 169 8 129 3 99 30 76 96 60 13 47 34 37 55 30 24 13 19 53 15 91 13 03 10 74 8 89 7 40 6 20 VOLTAGE 4 48 V 4 33 V 4 16 V 3 95 V 3 734 V 3 487 V 3 22 V 2 95 V 2 67 V 2 40 V 2 14 V 1 89 V 1 64 V 1 45 V 1 27 V 1 10 V 0 96 V ...

Page 46: ... there is a fan motor malfunction this process is repeated 3 times If the fan motor is determined to be defective the error code will be shown in the display for 30 minutes At this point the process will be repeated until the fan motor operates normally If normal operation is achieved the error display is erased and the MICOM is reset automatically No signal Error Display 15s 10s 15s 10s 15s Norma...

Page 47: ...et a ohmmeter to the 2 housing pin Measure the 2 pin connected to Fuse M If the ohmmeter indicate below 0 1ohm fuse m is a good condition But if infinite the part is bad How to Measure Sensor Set a ohmmeter to The 2housing pin Measure the 2 pin connected to Sensor If the ohmmeter indicate 11 at room temperature Sensor is good When check the ohm at other temperatures Check the sensor manual Standar...

Page 48: ...resistance How to Measure Set a ohmmeter connect to The 2 housing pin Measure the 2 pin connected to Sheath Heater If the ohmmeter indicate V øV Watt R is good condition ex when watt 350w voltage 115v R 115 ø115 350 38 But if the ohm meter indicate infinity the Sheath heater is bad Standard Sheath heater at all temperature Test Point 1 to 2 Ressult 34 42 1 2 ...

Page 49: ... 49 11 3 Door Heater Assembly Function The heater is designed to prevent the door from sweating How to Measure Standard Test Point 1 to 2 Ressult 2 3 2 9 1 2 3 5 8 9 4 6 7 ...

Page 50: ...ct operate on and off moving plunger of door switch up and down How to Measure Switch Freezer Switch Refrigerator Check the resistance between connectors 1 2 and 3 4 It means check whether or not applying an electric current If there is resistance the switch is good Standard Beep Beep Multimeter beep Switch F R Nomal Beep or 0 Push the button Plunger None Button Plunger 1 2 3 4 3 4 2 1 1 2 3 4 ...

Page 51: ... DC Motor Function Dispenser DC Motor When customer push the dispenser button Pull duct door and abstract from ice bank How to Measure Standard Dispensor DC Motor Dispenser DC Motor Test Points 1 to 2 Result 9 9 12 1 1 2 ...

Page 52: ...Solenoid Test Points 1 to 3 Result 31 1 42 09 Separate the housing Measure the resistance between 1 and 2 Check the resistance between connectors In door motor 1 2 and In door motor 1 3 It means check whether or not applying an Electric current If there is resistance it means the geared motor or solenoid is not inferiority 1 2 3 1 1 2 Separate the housing Measure the resistance between 1 and 3 1 2...

Page 53: ... the damper is closed the chill rooms temperature will rise How to Measure Damper Circuit extension Check the Standard Damper Test Points Red and Yellow Result 373 456 Test Points Blue and White Result 373 456 Check to see if there is electrical current if there is resistance the damper is good 1 Blue 1 Blue 2 Red 3 White 3 White 1 3 Check the 2 4 Check the 1 3 3 Yellow ...

Page 54: ...r lamp assembly The lamp socket supply electric source to lamp also How to Measure Standard Check the resistance between connector of housing and connector of lamp socket It means check whether or not applying an electric current If there is resistance it means the lamp socket is good Test Points 1 to 2 and 3 to 4 Result 0 1 2 3 4 ...

Page 55: ...Sensor Function Flow Sensor in machine room Count the water quantity from city water to water filter in refrigerator How to Measure Standard Flow Sensor in machine room Test Points Red wire to Black wire Result 4 30 ...

Page 56: ...ink2 LED blink6 Reset Reset Reset Reset LED blink 1 LED blink 7 Replace Driver PCB Comp Check Replace Driver PCB LED blink 5 LED blink2 Heavy Repair Heavy Repair Comp Work Comp Check Replace Comp Comp Work Comp Check Harness Check Leakage Recheck Reset LED blink6 Heavy Repair Heavy Repair Recheck Replace Driver PCB Comp Work Comp Check Refrigerant leak IPM output 80V 20 Refrigerant leak Recheck Fi...

Page 57: ...e Measure the DC low voltage that supplies the inverter circuit E Inverter A Inverter FC75LBNA Driver PCB located in machine room PCB Malfunction Check Step1 Open PCB Cover Step2 Check Driver PCB Step 3 Check Fuse visual inspection Step 4 Check DC High Voltage Multi Tester Spec about 330V DC Step 5 Check DC low voltage Multi Tester Spec A Point 15V B Point 5V Step 6 Check LED Blink See Check B LED...

Page 58: ...ssor is receiving voltage from IPM In order to determine whether the compressor is operating normally check the output voltage during the refrigeration cycle After initial power up when the compressor begins to operate wait 10 minutes before checking The compressor is operating normally if the voltage is greater than 80V IPM Output check ...

Page 59: ...Protection logic Check B Blink 2 times Stroke Trip Check B2 Compressor Doesn t work Y N Compressor Works Intermittently Capacitor Spec Check C Compressor Damage Check C Replace Capacitor Replace Compressor N N Reset Power Stroke Trip Occur Y Repeat Check Procedure Harness Connecting Check C Fix Harness N N Cycle Check E Fix Cycle Replace Driver PCB OK NG Purpose Prevent abnormally long piston stro...

Page 60: ...off and tries to restart within 2 5 minutes B4 LED blinks six times then repeats Current Trip A E Inverters Blink Blink Blink Blink Blink Blink OFF Protection logic Check B Blink 6 time Current Trip Check B4 Compressor Intermittently works Y Capacitor Spec Check C2 Compressor Damage Check C3 Replace Capacitor Replace Compressor NG NG Reset Power Y Current trip Occur Y Repeat Check Procedure IPM Ch...

Page 61: ...k B5 Compressor Doesn t work Y N Repeat Check Procedure Replace Drive PCB N Y Check IPM visual inspection turn off Short Test Point A Power Reset Compressor Damage Check C3 Replace Compressor NG Y Modify Purpose Prevent high current due to IPM Short Cause Damaged IPM Dead Short Test for a dead short at Point A with a VOM Logic Compressor is forced off and tries to restart in 2 5 minutes A ...

Page 62: ...tance at Point B 6 8ohm Resistance at Point D 6 8ohm Replace Compressor Problem B D Check wiring to compressor Y N N Y Y Y N N Check Compressor terminals Harness Problem Y N Y Measure the resistance at each point except point C Dead short check measure the resistance between power line in compressor and earth ground in refrigerator Inf Ohm FC150NAMA Multi Tester FC75LBNA Capacitor Spec 450V 18 F 5...

Page 63: ...fore oil will flow out with the refrigerant at leak point Ê Ê Temp of compressor and discharge line is normal to slightly higher High side pressure is normal to slightly higher than normal conditions This is because condenser cannot condense the air that is trapped in the condenser The high side pressure and temperature will not mimic the low side pressures and temperatures Over charging Refrigera...

Page 64: ...oubleshooting Step 1 Open PWB cover Step 2 Check for blinking frequency of LED PWB If compressor is normal it does not blink Refer to the next page to find out what actions to take according to how many times LED blink ...

Page 65: ...r the second action replace compressor Circuit over current error Or cycle error 1 After resetting power check if it is running normal 2 If the same symptom arises after the first action 3 If the same symptom arises after the second action replace compressor PCB parts defect IPM 1 After resetting power check if it is running normal 2 If the same symptom arises after the first action replace PCB 1 ...

Page 66: ...rly Seal liquid foods with wrap Put in foods after they have cooled down Don t open the door too often and close it firmly Condensation forms in the Exterior Case Check if the ambient temperature and humidity of the surrounding air are high Is there a gap in the door gasket Wipe moisture with a dry cloth It will disappear in low temperature and humidity Fill up the gap There is abnormal noise Is t...

Page 67: ...ing of the Refrigerant MOISTURE CLOG Cooling operation stops periodically Flowing sound of refrigerant is not heard and frost melts Lower than ambient temperature Cooling operation restarts when heating the inlet of the capillary tube CLOGGED BY DUST COMP RESSION Freezer and Refrigerator don t cool Low flowing sound of refrigerant is heard and frost forms in inlet only A little higher than ambient...

Page 68: ...Test Very Slow None Equalization Test Very Fast Fast Very Fast Inefficient Compressor Partial Restriction Complete Restriction Condenser Temperature Cap Tube Sound Yes No Air Low Side Leak Loss of Change Very Slow Faint Hotter than Normal None to Weak Room Temperature Compressor Not Pumping Trace of Oil Undercharge The equalization test is trying to restart a compressor using a start kit after it ...

Page 69: ...ply water to the ice tray by operating the solenoid valve To force water to supply to the ice tray or check icemaker s condition press and hold the FILL Key for about 3seconds In the test mode The icemaker will run through 3 stages step by step Harvest Fill water Ice making To reset the icemaker s operation set the power switch OFF position and back it to ON position Icemaker Unit Power Switch Ice...

Page 70: ... passed to make one series of ices after water comes into icemaker Test Mode should not be carried out before checking below 13 2 3 Fill Park Position Once the normal harvest mode has been completed the water solenoid will be activated Not making ice Water Yes Yes No No No Temperature Time Is Icemaker s tray filled with water or Ice Is measured temperature below 10 F in the icemaker compartment Ho...

Page 71: ...agnosed Follow the procedure step by step to check to see if icemaker and Ice detecting sensor is working normally 1st STEP Icemaker Unit Diagnosis Press the fill key for about 3sec If the icemaker runs 2 stages of harvest and filling water step by step It means icemaker s mechanism is normal Caution Be sure that the ice tray is not filled with water before pressing fill key Icemaker Unit Fill Key...

Page 72: ...arm air could get into the compartment and make ices get stuck Replace the cap duct with new one In door geared motor doesn t work Resolution Change the in door geared motor and test it The water comes out of fill cup and the water get into the ice bin Resolution The water pressure from shutoff valve is too high Recommend to use regulator to the customer and close the shutoff valve slightly Clogge...

Page 73: ...splay temperature mode can be changed from F to C or C to F by pressing and holding the FRZ TEMP and the REF TEMP keys at the same time for over 5 seconds 14 1 3 Lock function dispenser and display button lock 1 When the refrigerator is first turned on the buttons are not locked LOCK is deactivated with no light on 2 To lock the display the dispenser and the control panel press and hold the LOCK b...

Page 74: ...n again 3 Ice plus function automatically turns off after a fixed time passes 4 If you want additional power save you can turn on energy saving some heater off for anti dew 5 To turn on or off the energy saving function press Ice plus Energy saving Button for more than 3 seconds 6 We recommend using energy saving function when you go out for quite a long time and are out of the rainy season 14 1 6...

Page 75: ...he display mode and cancel it 1 With the refrigerator door open keep pressing the Refrigerator Temp Button and ICE PLUS Button more than 5 seconds then it goes to the display mode with Special Beep Sound With Special Beep Sound 2 Perform the same way again to cancel the display mode 3 All Freezing unit will be turned off at display mode Exceptions Lamp Display 14 1 7 CONTROL OF FREEZER FAN MOTOR 1...

Page 76: ...ly start upon the selected Auto Pantry temperature control 2 You can adjust the Pantry control with three different temperature ranges by pressing the Temp Selector button 14 1 14 Defect Diagnosis Function 1 Automatic diagnosis makes servicing the refrigerator easy 2 When a defect occurs the buttons will not operate but the tones such as ding will sound 3 When the defect CODE removes the sign it r...

Page 77: ...S17 103C 315A 315C 315B 106A 290A 106A S14 313A 411A 500A 500H 410J S02 271D S10 145B S11 406D B01 610D 402A S03 207A 503F 315B 315C B04 120B 249C 262B 262H 249D 316A 310B 312A 300A 314A 317A 303A 318A 304A 309B 329C 323B 319A 319C S20 420A 312C 302B 400A 408A 316B 406B 404A 405J B02 B02 624A 624C 624G 626A 603C 603E 624E S03 207B 402A 409B 105A 105D 146G CASE PARTS CAUTION Use the part number to ...

Page 78: ...133B 131A 133B 145F 133B 136B 237C 136A 133A 132P 145C 136C FREEZER PARTS CAUTION Use the part number to order part not the position number ...

Page 79: ... 142D 142B 141A 141C 141B 141A 141C 141B 141A 141C 141B 142A 161B 151B 161C 146E 141D 154A 162B 145D 162A 161A 151A 151C REFRIGERATOR PARTS CAUTION Use the part number to order part not the position number ...

Page 80: ...06 243D 243A 262E 244A 241C 241A 241B 233A 231A 212G B06 203A B06 250F 250K 212D B06 619B 603B 603C 200A 262C 262C 249K 250A 249J 250B 249F 250B 249E 249P 615A 312B 241K 241K 201A 267A DOOR PARTS CAUTION Use the part number to order part not the position number ...

Page 81: ...279B 276A 276B 405A 279I 279H 279J 402C 281A 279D 500C 279E 501A 279A 279C 281B 275A 276F 276G 501D 278C 278D DISPENSER PARTS CAUTION Use the part number to order part not the position number ...

Page 82: ...617A 625A 616G 623B 616J 616G 623B 616J 603C 616D 616D S31 616F 627B S31 619E 627A S31 603B 619A VALVE WATER TUBE PARTS CAUTION Use the part number to order part not the position number ...

Page 83: ...ICE MAKER ICE BIN PARTS LFX28978 CAUTION Use the part number to order part not the position number 600A 630F 630B 630A 630H 630G 630C 630Q 630E 630D 611A 612A 630J 606A 630J 608A ...

Page 84: ...MFL62188034 FEB 2010 Printed in Korea ...

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