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Service Manual is STRICTLY PROHIBITED unless you have obtained the prior written consent of the LG Electronics entity from which you received this Service Manual. The material covered by prohibition includes, without limitation, any text, graphics or logos in this Service Manual.
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For Authorized Service Technicians CONTENTS 1. impoRtant safety notice ........................... 4 2. specifications ................................5 3. featuRes and opeRation ............................ 6 4. paRts ....................................17 5. pRogRam chaRt ............................... 18 6. how to disassemble ............................30 7. tRoubleshooting methods .......................... 47 7-1.
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For Authorized Service Technicians CAUTION DISCONNECT POWER SUPPLY LINE BEFORE SERVICING RECONNECT ALL GROUNDING DEVICES IMPORTANT SAFETY NOTICE This service information is intended for individuals possessing adequate backgrounds of electrical, electronic and mechanical experience. Any attempt to repair this appliance may result in personal injury and property damage.
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For Authorized Service Technicians 2. SPECIFICATIONS ITEM SPECIFICATION Rated voltage / frequency ac 120v/60hz installation built-in place settings product dimension (in.) (w) x 24 ⅝ (d) x 33 ⅝ (h) product weight (lb.) 72-82 door color white, black, stainless steel, black sts, matte black tub material stainless steel control...
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Smart ThinQ™ Download the new LG smart phone app to set options, self-diagnose and troubleshoot problems with the appliance, and other useful features. Some of these functions use Wi-Fi or NFC (Near Field Communication) technology and require an NFC-equipped smart phone.
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For Authorized Service Technicians Control Panel for non-steam models (ldt779#**, ldp679#**, ldp567#**, ldt566#**) Power • : Control Lock • Press the Power button to turn power on and - The Control Lock feature helps prevent off. settings from being changed during a cycle. •...
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For Authorized Service Technicians Control Panel for non-steam models (ldf554#**) before 705xx Power • : Control Lock • Press the Power button to turn power on and - The Control Lock feature helps prevent off. settings from being changed during a cycle. •...
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For Authorized Service Technicians Control Panel for non-steam models (ldf554#**) after 705xx Power • : Control Lock • Press the Power button to turn power on and - The Control Lock feature helps prevent off. settings from being changed during a cycle. •...
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For Authorized Service Technicians Cycles Download Cycle Use a dedicated cycle downloadable via Wi-Fi or Select your desired cycle. NFC. Auto Machine Clean This cycle senses the soil amount and soil toughness This cycle is for cleaning the inside of the dishwasher. and is optimized to achieve the best cleaning.
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For Authorized Service Technicians Options High Temp Raises the main wash temperature to improve Select the desired cycle button and then select the cleaning. options for that cycle. Extra Dry Dual Zone Select the Extra Dry option for better drying This option automatically sets the spray intensity to performance.
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For Authorized Service Technicians Control Panel For Steam Models(LSDF9897**, LDT7808**, LSDT9908**) Power • : Rinse Aid Icon • Press the Power button to turn power on and - This icon illuminates when the rinse aid level is off. low. The LED automatically shuts off when the •...
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For Authorized Service Technicians Cancel • The drain pump activates and the cycle cancels. power turns off. • Press and hold Start for three seconds to activate. Start • To operate the machine, either press Start and close the door within four seconds or close the door and press Start.
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For Authorized Service Technicians Cycles Download Cycle Use a dedicated cycle downloadable via Wi-Fi or Select your desired cycle. NFC. NOTE Auto • Only the cycle code for the current Download cycle This cycle senses the soil amount and soil toughness appears on the appliance.
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For Authorized Service Technicians Options High Temp Raises the main wash temperature to improve Select the desired cycle button and then select the cleaning. options for that cycle. Extra Dry Dual Zone Select the Extra Dry option for better drying This option automatically sets the spray intensity to performance.
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For Authorized Service Technicians 3-3. TEST MODE CHECK PROGRAM Load and Checking points Door Times button BUTTON open/ Remark is pushed Display Load closed lighting "nC" will be n35/U00/ POWER All LEDs are displayed when 1 TIME Either NFC or Wi +START (Verstion) Module fails.
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For Authorized Service Technicians 4. PARTS Exterior Parts Control Panel & Door Handle Control Panel Front Cover Door Handle Lower Cover Front Cover Shipping Brace Lower Cover Safety Cover Shipping Brace SignalLight (some models) Safety Cover Base SignalLight (some models) Leveling Feet Base Leveling Feet...
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For Authorized Service Technicians 5. PROGRAM CHARTS (SCHEMATIC DIAGRAMS) Smae to Auto Strong Same to Normal Strong - 18 -...
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For Authorized Service Technicians <For Steam Models> Same to Auto Strong Same to Normal Strong Same to Normal Strong - 26 -...
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For Authorized Service Technicians 6. HOW TO DISASSEMBLE 1. Lower Cover 1) Remove the front 2 screws. - 30 -...
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For Authorized Service Technicians 2-1. Front Cover Assembly ※ For models: LUDP8997** LDP6797** LDP5676** LDF5545** ① Open the door. ② Remove the 6 screws around front cover assembly. ※ For models: LDT7797** LDT5665** LSDF9897** LDT7808**, LSDT9908** ① Open the door. ②...
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For Authorized Service Technicians 2-2. Control Panel Assembly ※ For models: LDP6797** LDP5676** LDF5545** ① Remove the 6 screws. ② Disconnect the wire connections. ③ Remove the handle.. ※ For Model: LUDP8997** Remove front cover screws, then follow steps 1-3 above. 2) Removing Handle Hook Screw...
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For Authorized Service Technicians 2-3. Door Liner Assembly Blower Assembly Dispenser Fan Motor ① Remove the screw. ② Remove the vent from Fan motor. ③ Disconnect the connector. ④ Open the Door. ⑤ Remove the Blower cover - Insert flat head screwdriver in hole (A). - Rotate flat head screwdriver slowly.
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For Authorized Service Technicians Assembling New Dispenser ① Verify the status of the flanges on the inner door. ② Place the support jig then insert the new dispenser. ③ Make sure that all flanges fit properly into the dispenser hooks. ※...
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For Authorized Service Technicians 2-4. Door Spring Replacing Door Spring Roller Rope ① Pull the Rope and Spring. Spring ② Remove the Rope from the Roller. ③ Remove the Spring from the Base. Base 2-5. Door Liner Replacing Door Liner ①...
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For Authorized Service Technicians 3. Lower Frame ① Remove 2 screws. ② Press the holder hook as shown in Overflow Hose figure. ③ Remove the Harness Holder. ④ Remove the Overflow Hose from the Lower Frame. ※ For LUDP8997** Model, Harness Remove the insulation sheet, then Holder...
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For Authorized Service Technicians 4. Tub Assembly Removing Racks (2-Rack Models) ① Slide all racks forward to remove. ※ For This Model Only (LDT5665**, LDF5545**) Removing Racks (3-Rack Models) ① Remove all Racks. ※ For This Model Only (LUDP8997**, LDT7797**, LDP6797**, LDP5676**, LSDF9897**, LDT7808**, LSDT9908**) - 37 -...
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For Authorized Service Technicians ※ Removing Gliding Upper Rack Rear Hook ① Insert a tool to widen the space between the hooks at the front of the rack while pulling up on the rack to Front Hook disengage it. ② Grab the Rack and push it back to remove rack from 2 rear hooks.
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For Authorized Service Technicians 3-1) Removing Air Guide Assembly Air Guide Air Guide ① Turn the Air Guide Nut counterclockwise. ※ Take care not to lose the rubber packing around the air guide assembly. ② Disconnect the connector. ③ Remove the Clamp on the Inlet Hose. ④...
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For Authorized Service Technicians 6) Removing Main PCB ① Press the hook and remove the PCB. ② Remove the screw and take the PCB Cover off. ③ Disconnect the connector. ※ Use care and move slowly when pulling out the main PCB. PCB Cover Main PCB ※...
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For Authorized Service Technicians 7) Casing Assembly, Pump ① Lay the product down on the floor. ※ Lay down towels first to protect floors from leakage. ② Remove the Base Cover. ③ Remove the wire on the Motor. ④ Disconnect the connector. ⑤...
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For Authorized Service Technicians 8-2) Removing Hinge Supporter ① Remove the Hinge Supporter screw. ② Remove the Hinge Supporter from Base Hook 8-3) Removing Rail Assembly (all other models) ① Detach the Glide Rail from the Front Hook ② Push the Glide Rail slightly backwards ③...
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For Authorized Service Technicians Rear Hook Detail View Rear Hook ※ Reassembling New Glide Rail ※ For This Model Only (LUDP8997**, LDT7797**, LDP6797**, LSDF9897**, LDT7808**, LSDT9908**) ① Align the Glide Rail holes and the Hooks ② Pull on the Glide Rail to fully assemble it Front ③...
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For Authorized Service Technicians 5. Sump Assembly 1) Removing Vario Motor & Cam ① Remove 2 screws for Vario Motor Vario ② Pull the Vario Motor/Cam and Micro Motor switch. Vario Micro 2) Removing Soil Sensor Switch ① Remove the wire connections. Soil ②...
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For Authorized Service Technicians <Steam Model> 1. Sump Assembly 1) Removing Steam ball valve ① Remove 2 screws. ② Remove the Clamp. ③ Pull the Steam ball valve. 2) Removing Steam Nozzle Hose ① Remove the Front Cover. ② Remove the Duct. ③...
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For Authorized Service Technicians <Steam Model> 2. Door Liner Assembly 1) Steam nozzle ① Remove the 4 Screws. ② Pull the Steam nozzle and Bracket. - 46 -...
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For Authorized Service Technicians 7. TROUBLESHOOTING METHODS 7-1. TROUBLESHOOTING ACCORDING TO DISPLAYED ERROR MESSAGE POSSIBLE CAUSE ERROR MESSAGE REMEDY FOR ERROR OCCURRENCE 1) The Water Supply Tap is closed. 1) Open the water supply tap. 2) Wiring connection is OK? 2) Check and reconnect the wire.
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For Authorized Service Technicians 1) The Inlet Valve is damaged. 1) Replace the Inlet Valve. EXCESS ERROR 2) The Controller is damaged. 2) Replace the Controller. 3) After Replace the PCB, still same 3) Replace the Hole Sensor. Error code is displaying. displayed Condition Water fills above normal...
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For Authorized Service Technicians 7-2. TROUBLESHOOTING METHODS How to Check Water supply (LQC Mode) - Press ‘Power + Start’ - Press ‘Start’ 5 times. (Check supplying sound) - Press ‘Power’ (Turn off the dishwasher) - 49 -...
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For Authorized Service Technicians ※ For AE errors, see the checklist below and provide more details on the repair report under Technical Remarks. 1) Check that unit is properly leveled. Use a digital level to check proper level. 2) Check that the mounting bracket is properly installed. 3) Determine what kind of detergent and rinse-aid are being used.
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For Authorized Service Technicians No Power Is the supplied voltage Check the Reconnect the 120V AC(+10%, -15%) fuse or reset connector or repair Is the connector connected to Main PCB the circuit the harness Assembly disconnected or disassembled? breaker. Replace the Alternate Is Chip LED on while the power is on? main PCB...
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For Authorized Service Technicians Washing result is not satisfactory. After washing, are there white Using a wash booster will help deposits on the dishes or inner remove spots, residue and hard water (white) film. tub? After washing, are there Reduce the amount of Rinse aid. any streaks on the dishes or inner tub? After washing, are there...
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For Authorized Service Technicians Drying result is not satisfactory. After washing, are there Reduce the amount of Rinse aid. any streaks on the dishes or inner tub? After washing, are there Increase the amount of Rinse aid. water drops on the dishes or inner tub? a) Does the upper nozzle fit properly Is the drying result of...
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For Authorized Service Technicians 7-3. TROUBLE DIAGNOSES AND REPAIR BY SYMPTOM No Power on when the power button pressed. • Re-connect the power connection. The Power connection is correctly connected. • Was there a power failure? The Fuse or • Replace the Fuse or Circuit Breaker of house. Circuit Breaker of house is O.K? The Power Switch or...
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For Authorized Service Technicians The Wash Pump/Motor does not run. • close the Door tightly. The Door is tightly • Check the Door Switch in Latch Handle. closed? • Re-connect the wiring connections related to the The Wiring connections are OK? Washing Motor.
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For Authorized Service Technicians Power Button not automatically off after operation. Make sure the button is not blocked by foreign materials. Check the Power Switch.(Replace it, if necessary.) Check the Controller.(Replace it, if necessary.) - 28 - - 28 - - 62 -...
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For Authorized Service Technicians 8. INSTALLATION INSTRUCTIONS Preparing Cabinet Opening WARNING Don't use existing holes unless they are in the dishwasher opening. An opening may be needed on both sides to route plumbing and electrical drain hose may be damaged by being crushed connections.
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For Authorized Service Technicians Preparing Electrical Wiring Preparing Water Supply Connection Operate this appliance with the correct voltage as shown in this manual and on the rating plate. Make sure the house water supply is turned off before connecting the dishwasher water lines. branch circuit which is protected by a time delay Connect the dishwasher to a hot water supply including a ground wire.
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For Authorized Service Technicians Preparing Dishwasher Removing Lower Cover Remove the two screws attaching the lower Removing Rear Plastic Shipping cover to the dishwasher. Brace Remove the lower cover from the base. Remove the insulation pad from behind the access panel. NOTE Do not pull or lift the dishwasher using the handle;...
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For Authorized Service Technicians Attaching Mounting Hardware Sliding Dishwasher into Cabinet For countertops made of wood or other material installation brackets. Slide the dishwasher carefully into the cabinet opening. Insert the installation brackets into the slots in the upper frame. Make sure the drain hose inside the cabinet is not kinked or pinched.
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For Authorized Service Technicians Leveling the Appliance Check that dishwasher is level. Attach level on top front opening of tub from side to side. front legs and adjust the front of the tub. Attach level on front side of tub. Turn the front legs clockwise to raise the front of the tub and counter-clockwise to lower it.
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For Authorized Service Technicians Securing Dishwasher to Connecting Drain Hose Countertop For countertops made of wood or other material that 40" Method 2. (1016 mm) max. 12" (305 mm) NOTE min. from falling down into the pump. Use a magnetic screwdriver. Method 1 (not supplied).
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For Authorized Service Technicians NOTE Connecting to Disposal or Waste Tee with Air Gap dishwasher will not be able to drain properly. Remove the knockout plug with a hammer and screwdriver. Connecting to Disposal with No Air Connect end of the drain hose to the air gap with hose clamp provided.
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For Authorized Service Technicians Connecting Water Supply Connecting Power copper tube into the elbow. Tighten the compression nut and make sure that the line is not kinked or pinched. NOTE The best location for the electrical conduit is on the right side of the back wall.
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For Authorized Service Technicians Final Check Error Code Possible Cause and Solution Drain hose kinked or pinched. Turn on electrical power. Feed the drainage and supply Turn on house water supply. hoses through the hole under the sink. Then gradually slide the Make sure the door opens and closes smoothly.
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For Authorized Service Technicians 10. WIRING DIAGRAM 10-1. WIRING DIAGRAM LSDT990 - 101 -...
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For Authorized Service Technicians 10-2. MAIN PCB - 102 -...
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For Authorized Service Technicians 10-3. DISPLAY PCB - 103 -...
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For Authorized Service Technicians 10-4. MCU PCB ※ For This Model Only (LDT7797*,LDT5665**) - case1 LSDF9897**,LDT7808**,LSDT9908** - case2 - 104 -...
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For Authorized Service Technicians ※ For This Model Only (LUDP8997**) - 105 -...
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For Authorized Service Technicians Appendix - 106 -...