Service Manual Model No.: LET40T3 CONTENTS Chapter 1.General Information 1-1. Document Information ............... 3 1-2. General Guidelines ................3 1-3. Important Notice ................... 3 1-3-1. Follow the regulations and warnings ............. 3 1-3-2. Be careful to the electrical shock ............3 1-3-3.
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Service Manual Model No.: LET40T3 4-3-1. Function description:................14 4-3-2. Connector definition: ................14 4-4. LCD Panel ..................... 15 4-4-1. Function Description: Display the signal..........16 4-4-2. Connector definition: ................16 Chapter 5. Installation Instructions 5-1. External Equipment Connections ..........
Service Manual Model No.: LET40T3 Chapter 1.General Information 1-1. Document Information Document format: Adobe PDF Author: Compiler: 1-2. General Guidelines When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit.
Service Manual Model No.: LET40T3 techniques should be used to help reduce the incidence of component damage caused by electros static discharge (ESD). Electrostatically Sensitive (ES) Devices Some semiconductor (solid-state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor "chip"...
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Service Manual Model No.: LET40T3 a. Removing or reinstalling any component, circuit board module or any other receiver assembly. b. Disconnecting or reconnecting any receiver electrical plug or other electrical connection. c. Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.
Service Manual Model No.: LET40T3 13. Use only an anti-static type solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ES devices. 14. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
Service Manual Model No.: LET40T3 1-4. How to Read this Service Manual 1-4-1. Using icons: Icons are used to attract the attention of the reader to specific information. The meaning of each icon is described in the table below: Note: A “note”...
Service Manual Model No.: LET40T3 Chapter 2. Specification 2-1. Specification list Model LET40T3 Screen size 40 inch Aspect ratio 16:9 Resolution 1920*1080 Response Time(ms) 6 ms Angel of view Contrast 5000:1 Brightness 450cd/m2 OSD language English etc. Color system PAL\SECAM...
Service Manual Model No.: LET40T3 Back Side Chapter 3. Disassemble and Assemble 3-1. Remove the Stand 1. Lay down the unit so that back cover faces upward 2. Remove the Five screws from the back cover which are indicated with the circles in the picture above.
Service Manual Model No.: LET40T3 3-2. Remove the Power Cord 2. Then remove the back cover from the unit. Remove the screw indicated by the red circles in below picture. Then remove the power cord. 3-4. Remove the Mainboard Remove the five screws indicated by the red circles in below picture.
Service Manual Model No.: LET40T3 3-8. Remove the Stand backstop Remove the six screws indicated by the red circles in below picture. Take out the stand backstop. 3-6. Remove the Keypad The Keypad is conglutinated with front frame , just uncover the keypad gently.
Service Manual Model No.: LET40T3 Chapter 4. Location of Controls and Components 4-1. Board Location Parts number Description A Board 0094001076AD LCD Panel B Board 0094001897 Power Board C Board DC19B0E0400M Mainboard (0090723445) 4-2. Main Board CN10 CN27 CNB3 CNB4...
Service Manual Model No.: LET40T3 4-2-1. Function Description: Main Board Process signal which incept from exterior equipment then translate into signal that panel can display. 4-2-2. Connector definition Main board connector Speaker connector (CN27) Keypad Connector (CNB3) Pin number Signal name...
Service Manual Model No.: LET40T3 4-3-1. Function description: To supply power for Mainboard, Panel. 4-3-2. Connector definition: Pin number Signal name Pin number Signal name Pin number Signal name +12V +12V +12V BL-ON/OFF 5VSTB STATUS E-PEM E-PWM PW-ON/OFF PB-ON/OFF 4-4. LCD Panel...
Service Manual Model No.: LET40T3 4-4-1. Function Description: Display the signal. 4-4-2. Connector definition: CN1 Connector Pin number Symbol Description DC Power Supply DC Power Supply DC Power Supply DC Power Supply DC Power Supply Ground Ground Ground Rx1[0]N LVDS Signal -...
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Service Manual Model No.: LET40T3 Pin number Symbol Description Rx3[0]N LVDS Signal - Rx3[0]P LVDS Signal + Rx3[1]N LVDS Signal - Rx3[1]P LVDS Signal + Rx3[2]N LVDS Signal - Rx3[2]P LVDS Signal + Ground Rx3CLK- LVDS Clock - Rx3CLK+ LVDS Clock +...
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Service Manual Model No.: LET40T3 CN2 Connector Pin number Symbol Description DC Power Supply DC Power Supply DC Power Supply DC Power Supply DC Power Supply Ground Ground Ground Rx2[0]N LVDS Signal - Rx2[0]P LVDS Signal + Rx2[1]N LVDS Signal -...
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Service Manual Model No.: LET40T3 Pin number Symbol Description Rx4[1]P LVDS Signal + Rx4[2]N LVDS Signal - Rx4[2]P LVDS Signal + Ground Rx4CLK- LVDS Clock - Rx4CLK+ LVDS Clock + Ground Rx4[3]N LVDS Signal - Rx4[3]P LVDS Signal + Rx4[4]N...
Service Manual Model No.: LET40T3 Chapter 5. Installation Instructions 5-1. External Equipment Connections Accessories Batteries Remote Control Antenna Connection: Connect one end of a coaxial cable (not included) to the ANT IN jack on the back of your TV/DVD combo, then connect the other end of the cable into the antenna or cable TV wall outlet.
Service Manual Model No.: LET40T3 If you need to split the antenna signal to connect two TVs, install a two-way splitter. Choose Your Connection There are several ways to connect your television, depending on the components you want to connect and the quality of the signal you want to achieve. The following are examples of some different ways to connect your TV with different input sources.
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Service Manual Model No.: LET40T3 Connecting a VCR with an S-Video cable An S-Video connection provides better video than a standard AV connection. To connect a VCR with an S-Video cable: 1. Make sure that your TV/DVD combo and the VCR are turned off;...
Service Manual Model No.: LET40T3 Connecting an HDMI device An HDMI connection provides the best video and audio,An HDMI cable carries both video and audio,so you do not need to make an audio connection. To connection HDMI device: 1 Make sure that your TV/DVD combo and the HDMI device are turned off.
Service Manual Model No.: LET40T3 Supported video modes for a computer Mode Resolution Line frequency(KHZ) Frame frequency 640*480 31.5 SVGA 800*600 37.9 1024*768 48.4 Notes: If the computer dose not support one of the following videos, you may need to replace or add a video card.
Service Manual Model No.: LET40T3 Cable sample HDMI Cable (not supplied with the product) HDMI to DVI Cable ( not supplied with the product) Analog Audio Cable (Stereo to RCA type) (not supplied with the product) Connecting Headphones You can connect a set of headphones to your set if you wish to watch a TV program without disturbing the other people in the room.
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Service Manual Model No.: LET40T3 TO USE AC POWER SOURCE Use the AC polarized line cord provided for operation on AC. Insert the AC cord plug into a standard polarized AC outlet. NOTES: ■ Never connect the AC line cord plug to other than the specified voltage.
Service Manual Model No.: LET40T3 Chapter 8. Measurements and Adjustments 8-1. Service Mode 8-1-1.How to enter into Service Mode The way to the factory mode menu: 1st, press menu, 2en, input 8893, Finished these operations ,system will be into the factory mode menu.
Service Manual Model No.: LET40T3 8-2-2. Video Color Temperature This page is control the Color Temperature, and the picture size. Picture Mode This page is control the picture effect , like Brightness,contrast,color,sharpness.
Service Manual Model No.: LET40T3 8-2-3. Audio This page is control the sound effect ,from 100Hz to 10KHz. 8-2-4. Software UpDate NOTE : After software update ,turn to the Factory In this page , you just consider the software Setting 1 page reset all.
Service Manual Model No.: LET40T3 Chapter 9. Trouble shooting 9-1. Simple check Verify if the television is properly plugged Verify if the television is properly supplied power No picture/ No sound Verify if electricity is available. Verify if correct signals are input...
Service Manual Model No.: LET40T3 9-2. Power Supply Board Failure Check. State:No picture First,check cables which connect with PSU,then check as follows Check input voltage voltage: +5VSB----POWER ON(2.6V) -----+12V +12V CN10 Power +12V 5VSTB PB-ADJUST R350 PW_ON/OFF-INV R341 PB-ON/OFF 5VSTB...
Service Manual Model No.: LET40T3 9-3. Mainboard Failure Check Symptom: No Sound No Sound (All Mode) Fail Check the input Change Source input Source Pass Fail Check Re-soldering or change input/output IC U13 Of IC U13 of Main Pass Fail...