Saturday 11 April 2020

REPAIR / SERVICING TV DAEWOO U43V890VTE

Technical description and composition of the DAEWOO U43V890VTE TV, panel type and applicable modules. The composition of the modules.
DAEWOO LED
Model: U43V890VTE
Chassis / Version: 40-MS88S2-MAC2HG
Panel: LVU430LGDXE0001
LED backlight: TCL43D08-ZC23AG-07 303TC430031
T-CON: 6870C-0738A
LED driver (backlight): integrated into PSU
PWM LED driver: MP3398A
MOSFET LED driver: PC015BD
Power Supply (PSU): DLBB449 REV0.3 SHG4301A09-101H (SHG4301A-101H)
PWM Power: OB5269CPA,
MOSFET Power: MDF10N60B,
MainBoard: 40-MS88S2-MAC2HG 1MS488ZZAEU.01
IC MainBoard: AUDIO: TAS5707
Tuner: DVB-T2 & SAT
Technical Specifications U43V890VTE
DAEWOO U43V890VTE
General repair guidelines for TV LCD LED
Possible malfunctions
- DAEWOO U43V890VTE TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
Typically, with such manifestations, the defect is caused by faulty elements in the main power supply module DLBB449. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, check the serviceability of power switches (MDF10N60B,) and rectifier diodes for possible breakdown (short circuit).
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers OB5269CPA,, in the absence of visible damage or explicit short-circuit between the terminals, are checked by replacing with new, or obviously working.
- There is no image, there is sound, all other functions of the TV work. When turned on, the image may sometimes appear for a second.
The most likely in these cases is a malfunction of the LED backlight. Usually the cause of the malfunction is in the breakage of the LEDs, or in the connectors of the LED strips, but sometimes the LED driver also turns out to be faulty.
To check the LED strips 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 transitions in forward bias, you can sometimes detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the 40-MS88S2-MAC2HG motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - AUDIO: TAS5707 with new or obviously good ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
The malfunction of the DVB-T2 & SAT tuner is established after checking the software and all supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
Attention to users! Self-repair of a DAEWOO U43V890VTE TV without the appropriate qualifications and necessary experience can lead to its complete non-repairability!


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    SHG4301A-101H DLBB449 Power supply


 The appearance of the MainBoard 40-MS88S2-MAC2HG is shown in the figure below:
40-MS88S2-MAC2HG
The appearance of the power supply
Main features of the DAEWOO U43V890VTE device:
The matrix (LED panel) LVU430LGDXE0001 is installed.
The matrix control uses the Timing Controller (T-CON) 6870C-0738A.
To power the backlight LEDs, a converter is used, combined with the power supply, controlled by the MP3398A PWM controller. As the power elements of the LED driver, keys of the type PC015BD are used.
The necessary supply voltages for all nodes of the DAEWOO U43V890VTE TV are generated by the DLBB449 power module, or its analogs using OB5269CPA microchips, and power switches of the MDF10N60B type,.
MainBoard - the main board (motherboard) is a 40-MS88S2-MAC2HG module, using AUDIO chips: TAS5707 and others.
The DVB-T2 & SAT tuner allows you to receive television programs and tune to channels.


 Brand: DAEWOO, Model: U43V890VTE.
Briefly from the TV: LCD, LED backlight, 42.5 ", 3840x2160, 4K UHD, DVR, there is a satellite tuner, sound: 16W, HDMI connectors: 3, Internet access, Wi-Fi, Smart TV.
Manufacturer: HORIZON plant, Belarus, Minsk, st. S. Kovalevskoy, 62. Developer: Dongbu Daewoo Electronics Corporation.
The composition includes MainBoard 40-MS88S2-MAC2HG 1MS488ZZAEU.01 and LCD-panel LVU430LGDXE0001.
Power Supply Unit (PSU) SHG4301A09-101H DLBB449 REV0.3 Power Supply.
Technical description
DAEWOO U43V890VTE LED TV with an LVU430LGDXE0001 LCD display, diagonal size 42.5 "(108 cm) in 16: 9 format. The required screen brightness of 240 cd / m² is provided by LED backlight LED. The LED display backlight is implemented in the model’s display technology. Viewing is possible movies in the highest possible UHD quality with a resolution of 3840x2160 pixels in the 4K UHD standard.The U43V890VTE TV model has built-in SMART software and the installed Android Operating System.
Connecting to a network can be done via Wi-Fi.
Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), DivX, MKV, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, VGA, HDMI x3, MHL, USB x2, Ethernet (RJ-45), Wi-Fi 802.11n, WiDi. An output for connecting headphones is provided. The digital tuner is capable of receiving television channels in the standards DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2.
Overall dimensions: with stand 969x622x222 mm, without stand 969x572x79 mm.
TV Weight: with stand: 8 kg, without stand: 7.9 kg.
Attention! The panel of the LVU430LGDXE0001 LED-TV DAEWOO U43V890VTE is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the surface of the screen to avoid damage to the LED panel!
It is also unsafe to get liquid on the screen. Sometimes one drop is enough if it flows down the glass onto the cables so that the TV becomes unrepairable.