Technical description and composition of the THOMSON T42E02HU-01B TV, panel type and modules used. The composition of the modules.THOMSON LED
Model: T42E02HU-01B
Chassis / Version: TP.MS18VG.P78
Panel: LVF420AUDX E8 V1
LED driver (backlight): integrated into MainBoard
PWM LED driver: OB3363QPA (OB3368QPA)
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.MS18VG.P78 (3MS82AX)
IC MainBoard: CPU: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2
Tuner: R620D
Specifications T49D21SF-01B
THOMSON T42E02HU-01B
General recommendations for TV LCD LED repair
Possible manifestations of defects
- The THOMSON T42E02HU-01B TV does not turn on, all signs of operability are completely absent. The indicators on the front panel do not light, do not blink, the TV does not respond to the remote control and control buttons.
A malfunction in such cases, first of all, should be looked for in the power elements of a switching power supply (SMPS) - a mains voltage converter (AC / DC), which in this TV model is combined with the MainBoard TP.MS18VG.P78 main board. In the absence of the necessary supply voltages in the secondary circuits of the converters, it is necessary to check the power switch and rectifier diodes for possible partial or complete breakdown.
In case of breakdowns of semiconductors in the secondary circuits, the converter, as a rule, can operate in an emergency mode in a short circuit mode, and in case of a short circuit in the power elements of the primary circuit, the mains fuse usually breaks off.
Breakdown of power switches in pulse sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency setting or damper, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM regulators (PWM) PWM SOT23-6, if they do not have visible damage to the case and an open short circuit between the pins, are usually checked by replacing.
- There is no picture, there is sound, it reacts to the remote control, the channels are switched. In some cases, the image appears when turned on and disappears immediately.
In some of these cases, the malfunction is caused by the lack of display backlighting. The reason may be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
To test the LED strips, in order to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED junctions in forward bias, you can sometimes detect the presence of a protective zener diode PN junction by connecting the probes in the opposite direction. If the zener diode is cut off or broken in K / Z, then the LED is faulty and needs to be replaced.
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.
Repair or diagnostics of the TP.MS18VG.P78 motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Often the MB (SSB) board must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - CPU: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2 and replace the failed chips with new ones. Some malfunctions can be associated with the use of BGA soldering technologies in modern Main Board. Usually such defects are detected by local heating of the chip.
If there is no reception of TV channels, but the TV is working properly from external devices, first of all, you need to check the supply voltage of the R620D tuner and update the software. I2C communication pulses must be monitored with an oscilloscope.
If THOMSON T49D21SF-01B has no picture, but there is sound, often the display backlight simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the LCD panel - a process that requires experience and qualifications from the master. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see the light through the holes in the panel case.
In this case, the panel may also be faulty - damage to strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But often the main board MainBoard turns out to be faulty, a software failure is also possible.
Then, first of all, it is necessary to check the panel supply voltage, the fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within normal limits, it is necessary to trace the passage of LVDS signals from the MainBoard with an oscilloscope, as well as synchronization signals to the loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
Attention to TV owners! Attempts to repair the THOMSON T42E02HU-01B on your own are not recommended by the manufacturer and can lead to serious negative consequences!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> THOMSON T42E02HU-01B, Main: TP.MS18VG.P78 (3MS82AX), Panel: LVF420AUDX E8 V1
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> THOMSON T42E02HU-01B Chassis TP.MS18VG.P78
To reduce the backlight current in LED drivers with OB3363QP (16 pin) controller, the total resistance of the resistors from pin 5 (ISET) to the case should be proportionally increased.
Additional MainBoard RepairThe appearance of MainBoard TP.MS18VG.P78 is shown in the figure below:
TP.MS18VG.P78
TP.MS18VG.P78 can be used in TVs:
THOMSON T42E02HU-01B (Panel LVF420AUDX E8 V1), THOMSON T32ED05U-01B T32ED05U (Panel LVW320CSDX E3 V7), THOMSON T32E02U-01B (Panel A320HE2A05-7A), THOMSON T40ED06HU T40ED06HU-01B (Panel LVF400SSDX E7 V2).
The main features of the THOMSON T42E02HU-01B device:
Installed matrix (LED-panel) LVF420AUDX E8 V1.
To power the backlight LEDs, a converter combined with the main board TP.MS18VG.P78 is used, controlled by the OB3363QPA PWM controller (OB3368QPA).
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using PWM SOT23-6 microcircuits.
MainBoard - the main board (motherboard) is a TP.MS18VG.P78 module, using CPU chips: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2 and others.
The R620D tuner provides reception of television programs and tuning to channels.
LED TV THOMSON T49D21SF-01B with LCD, diagonal size 49 "(124 cm) 16: 9 format. The declared brightness of the screen of 300 cd / m2 is provided by modern LED backlight LED. The ratio of maximum brightness to minimum (contrast) is not less 4000: 1 LCD panel uses Direct LED backlighting The design and technical capabilities of the TV allow viewing in high quality HD at a resolution of 1920x1080 pixels in graphics resolution in 1080p (Full HD). Supported media formats: MP3 , MPEG4, HEVC (H.265), Xvid, MKV, JPEG.
Speaker power of 10 W (2x5 W) is provided by two speakers. Uses NICAM stereo processing system and Sound Surround function.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, VGA, HDMI x3, USB x2. A headphone jack is provided. The digital tuner has the ability to receive television channels in the DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2 standards.
Overall dimensions: 1106x701x274 mm.
TV weight: 10.7 kg.
Attention! The panel of the THOMSON T49D21SF-01B LED TV is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.
