LCD TV Repair Case Histories

LCD TV Repair Case Histories

By: Preher-Tech www.preher-tech.com 1

Contents Akai....3 Element....5 Emerson....6 Hyundai....7 LG....8 Magnavox....10 Philips....12 Polaroid....13 Samsung....15 Sanyo....19 Sceptre....20 Sharp....21 Sylvania....22 Toshiba....24 Vizio....25 Westinghouse....26 Further Reading....28 Websites....32 Part and Tool Distributors....33 2

AKAI LCT2662Symptom: No power. Repair: Replaced eight 2200uF, 25V, three 3300uF, 35V and one 1000uF, 16V electrolytic capacitors on the SMPS board.

LCT2715Symptom: No power, standby 5V missing Repair: Replace both 1000uF, 16V electrolytic capacitors on the SMPS board.

LCT2785TASymptom: No power. Repair: Replaced 1000uF, 16V electrolytic capacitors on SMPS board. Locations EC18, EC19 and EC20.

LCT3201ADSymptom: TV shuts off and standby/power LED changes color. Repair: 3

Replace bad 1000uF, 35V electrolytic capacitors on SMPS board. Locations EC18, EC19 and EC20. LCT42Z6TMSymptom: As TV warms up the picture scrambles, then the TV shuts down. Repair: Replaced C320, 100uF, 35v capacitor , on the edge of the main board very close to two SMD regulators.

4

Element FLX3210Symptom: Standby/power LED lights blue but backlights don't come on. A red LED on the power/inverter board blinks off and on. Repair: Replaced two open capacitors on inverter board. Locations EC17 and EC18. Both were 10uF, 450V.

FLX3211BSymptom: No back lights Repair: Replaced capacitors EC17 and EC18 10uF, 450 volts on the inverter board.

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Emerson EWL20S5Symptom: TV turns on, back lights come on and then TV shuts down. Repair: Replaced inverter board.

LC320EM81Symptom: No power, standby/power LED blinks continually Repair: Replaced main board.

LC320EM8ANSymptom: No power Repair: Replaced shorted diode in power supply. Location D633.

6

Hyundai E260DSymptom: No power, standby/power LED not lit. Repair: Replaced capacitor C60 (.0022 IKV ceramic disc capacitor) in the standby section of the SMPS board. LC-23Y18Symptom: No power, power/standby LED flickering Repair: replaced bad 470uF electrolytic capacitor on the secondary side of the standby circuit on SMPS board.

7

LG 26LX1DSymptom: Wavy lines in picture Repair: Replaced two bad 100uF, 16V SMD electrolytic capacitors on the main board. Locations C708 and C704.

32lc2dSymptom: No back light Repair: Replaced electrolytic capacitors at locations C200 and C202, 3300uF, 10V and electrolytic capacitor Location C208 1000uF, 16volt on SMPS board. 32lc2dSymptom: Unit will fail when warmed up, no video just lines. Repair: Replaced bad electrolytic capacitors at locations C200 and C202, 3300uF, 10V and electrolytic capacitor at location C208, 1000uF, 16volt on SMPS board.

8

37LC2DSymptom: Might take many attempts to turn TV on. Repair: Replaced bad electrolytic capacitor at location C280, 1000uF, 16V and electrolytic capacitor at location C125, 4.7uF, 50V on SMPS board.

9

Magnavox 19MF337BSymptom: Flickering picture and loud audible noise from TV maybe be intermittent start. Repair: Replace bad electrolytic capacitors on SMPS board. Locations C12, C117 and C118, 1000uF, 16V and Location C175, 470uF, 16v.

37MF321D37Symptom: No power Repair: Replaced bad electrolytic capacitors on SMPS board. Two 2200uF, 50V and two 1000uF, 50V.

32MF231D/37Symptom: Standby/power LED lights but TV does not turn on. Repair: Replaced bad electrolytic capacitors on SMPS board. Locations C2079 and C2080 both were 1200uF, 35V.

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32MF338B/F7Symptom: Back lights flickering. Repair: Found D19940 shorted and replaced with an NTE506.

11

Philips 37MF331D/37Symptom: No power Repair: Replaced one 1200uF, 35V and one 2200uF, 25V electrolytic capacitor on SMPS board.

12

Polaroid FLM3732Symptom: Loud screeching noise from TV speakers Repair: Replaced bad electrolytic capacitors at locations C112 and C113, both 1000uF, 10V on SMPS board.

FLM3732Symptom: Standby/power LED comes on, no picture or audio and TV can not be turned off without unplugging. Repair: Replaced bad electrolytic capacitors on SMPS board. Both1000uF, 10V

FLM3738Symptom: Buzzing noise, Line through middle of picture and eventually no power. Repair: Replaced two 1000uF, 10V electrolytic capacitors on SMPS board.

13

FLM373BSymptom: Loud buzz in audio, goes away after a few minutes. Repair: Replaced bad electrolytic capacitors at locations C112 and C113. Both 1000uF, 10V.

14

Samsung LN26A450Symptom: No power Repair: Replaced bad electrolytic capacitor location CM861, 2200uF, 16V, only measured 400uF.

LN32B540P8DSymptom: No power or TV turns on but with no back light. Repair: Replaced shorted diode at location DP805.

LN40A650Symptom: Fan1 error displayed Repair: Replaced bad fan, sometimes cleaning the fan works as well.

15

LNS2651DX/XAASymptom: No power Repair: Replaced open .22 ohm resistor on the SMPS board at location RM801.

LNS4041DX/XAASymptom: Power cycles on and off before coming on, also may have some flashing pixels. Repair: Replaced bad electrolytic 1000uF, 10V capacitors on SMPS board.

LNS4051DSymptom: TV Immediately shuts down after being turned on Repair: Replaced four bad electrolytic capacitors, 1000uF, 10V. Locations CS806, CM811, CM812 and CM817 on SMPS board.

LNT3253HXSymptom: High Pitch Hum in Audio, TV still has picture and sound. Repair: Replaced bad electrolytic capacitors on main board. Locations CM861 and CM856. 16

LNT4061FX/XAASymptom: Set had vertical colored lines no OSD(On Screen Display) and no remote function Repair: Replaced bad electrolytic capacitors on SMPS board. Locations CM11, CM12, CM17 and CM16. 1000uF, 16V

LNT4661FSymptom: Takes a while to come on and when it is on, there are red dots all over the video Repair: Replaced bad electrolytic capacitors on SMPS board. Locations CS804, CV812 and CV813. All were 1000uF, 16V.

LNT4665FX/XAASymptom: Power relay continually clicks and the TV never comes on. Repair: Replaced bad electrolytic capacitors on the SMPS board. Locations CM852 and CM853. Both were 2200uF , 10V.

17

LNT4671FX/XAASymptom: The power relay and indicator LED continually cycle on and off. Repair: Replaced bad electrolytic capacitors on the SMPS board. Locations CM852 and CM853. Both were 2200uF, 10V.

LNT5271FX/XAASymptom: Dead Set Repair: Replace CM853 & CM852 , both 2200uF, 10V. Note, It is probably best to upgrade the working voltage from 10V to 16V.

18

Sanyo DP32746Symptom: Set would not turn on, all secondary supply voltages would fluctuate up and down. Repair: Replaced bad opto-isolator IC location D1622 on the power board.

19

Sceptre X32GV-KomodoSymptom: No power, sometimes standby/power LED will blink red. Repair: Replaced bad electrolytic capacitors, 470uF, 10V and 220uF, 35V on SMPS board. Locations CS118 and CS206.

20

Sharp LC37D43USymptom: No Back light Repair: Replaced fuse (F7502) rated T500ma on the inverter board.

21

Sylvania 6620LF4Symptom: No audio Repair: Shorted capacitor,100uF, 16V. Location C811.

6637LCTSymptom: No power Repair: Replaced shorted diode location D603 and open fuse location F601 on SMPS board.

LC200SL8Symptom: No power Repair: Replaced shorted diode location D902 on SMPS board.

22

LC320SL8Symptom: No power Repair: Replaced shorted diode at location D502 and open main fuse on SMPS board.

LD370SS8Symptom: DEAD Repair: Replaced shorted diode at location D633 on secondary side of SMPS board.

SSL2006Symptom: No power Repair: Replaced shorted diode on SMPS board. Location D636..

23

Toshiba 52RV530USymptom: Intermittent audio distortion and no audio when using HDMI input. Repair: Replaced main board.

37HLV66Symptom: Picture freezes but sound remains normal after about 30 minutes from turning on. Picture may change color as well. Repair: Replaced the Seine/signal board part number 75004721.

42LX196Symptom: One click no sound or picture, green LED lights then TV clicks off. Repair: Replaced bad electrolytic capacitor, 680uF and also replaced destroyed IC u1 on inverter inverter board.

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Vizio L37HDTVSymptom: Amber light comes on but never turns green TV does not turn on Repair: Remove SMD IC U26 near the reset tact switch on the main board. Install a glass switching diode (NTE519) cathode on pin 2 and anode on pin 3. This will also work on other Vizio models using the same IC.

VO47FHDTVSymptom: Set has no back light. Repair: Replaced 2 bad electrolytic capacitors, 680uF, 35V on inverter board. Also replaced one bad electrolytic capacitor, 680uF, 35V on SMPS board.

vp322Symptom: No power Repair: Replaced bad electrolytic capacitors. One 3300uF, 10V at location C232 and two 1000uF, 10V at locations C233 and C236 on SMPS board.

25

Westinghouse LTV27W2Symptom: TV losses picture and sound once warmed up. Standby/power LED stays blue Repair: Repaired bad solder connection on capacitor C310 on SMPS board primary side.

LTV27w7Symptom: No power but standby/power LED turns blue. Repair: Replaced shorted transistors Q1011 and Q1009. Also replaced open resistor R1010, .1 ohm.

LTV32W1Symptom: No power. Power LED turns blue to amber then off , may be intermittent Repair: Repaired bad solder connection on transformer T1 pin 4 on the SMPS board.

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LTV32W4HDCSymptom: Picture freezes. Repair: Replaced main board.

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Further Reading Some good books to further your electronics knowledge. Electronic and Electrical Servicing Consumer and Commercial Electronics 2nd edition, By Ian Sinclair and John Dunton

Electronic and Electrical Servicing Consumer and Commercial Electronics Level 3" 2nd edition, By Ian Sinclair and John Dunton

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How To Find Burnt Resistor Value, By Jestine Yong

LCD Monitor Repair, By Jestine Yong

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Testing Electronic Components, By Jestine Yong

Troubleshooting & Repairing Switch Mode Power Supplies, By Jestine Yong

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Troubleshooting Switching Power Converters: A Hands-on Guide, By: Sanjaya Maniktala

Switching Power Supplies A to Z, By: Sanjaya Maniktala

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Websites Some good websites for electronics information. Preher-Tech Blog Preher-Tech Electronics Tools and Tips Page LCD TV repair membership site Plasma TV repair membership site Projection TV repair membership site electronicrepairguide.com Jestine Yong's Blog fastrepairguide.com

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Part and Tool Distributors Here are the parts distributors I most commonly use to get all the parts I need for fixing LCD TVs. Suburban Encompass Mouser MCM And I also always like looking on ebay, I have bought many TV and electronic components on that site in general with great deals and I have only had great transactions so far. Only buy from reputable dealers. Places to purchase an ESR meterElectronic Repair Guide(also sells Ring Tester) Anatek(also sells Ring Tester) EVB Radio Devices(the ESR micro, which also checks capacitance) CCFL TestersHR-TL1040 LST01 Good place to buy affordable digital multimeters and analogue metersMultimeter Warehouse 33