Saturday 11 April 2020

REPAIR / SERVICING TV DAEWOO L32S635VKE

Technical description and composition of the DAEWOO L32S635VKE TV, panel type and applicable modules. The composition of the modules.
DAEWOO LED
Model: L32S635VKE
Chassis / Version: MSD3463-T4C1
Panel: K320WD82 // LC320DXY (SH) (A4)
LED driver (backlight): integrated into MainBoard
PWM LED driver: OB3350CP
MOSFET LED driver: AOD4286
Power Supply (PSU): integrated into MainBoard
PWM Power: LNK6777
MainBoard: MSD3463-T4C1
IC MainBoard: SPI Flash: MX25L6406E, Audio: TPA3110LD2
Tuner: ST43WS-2A-E
Technical Specifications L32S635VKE
DAEWOO L32S635VKE
General repair guidelines for TV LCD LED
Possible malfunctions
- DAEWOO L32S635VKE TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
The malfunction in such cases should be sought in the elements of the power source - the network voltage converter (AC / DC), which is located on the MainBoard MSD3463-T4C1 main board. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches and rectifier diodes of the converters for a possible short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more often breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM) LNK6777, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously working ones.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
Usually in such cases there is no backlight LED-panel (matrix). Often the cause of the malfunction is the lack of current in the LED circuit, for example, an open or short circuit, or a violation of the contact connections of the connectors.
To detect a break in the LED lines without disassembling the panel, a current source is required. It is impossible to open transitions connected in series with a simple multimeter; voltage of several tens of volts is necessary.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the motherboard MSD3463-T4C1 should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Board repair and replacement of SPI Flash chips: MX25L6406E, Audio: TPA3110LD2 are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If you suspect a malfunction of the ST43WS-2A-E tuner, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary voltage levels and pulses of data exchange with the processor via the I2C bus at the corresponding terminals of the tuner.
Attention! Users and owners of L32S635VKE TVs who do not have the appropriate qualifications, knowledge and experience are strongly discouraged from attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    MSD3463-T4C1 Power supply & LED-Driver.

FIRMWARE FOR SPI FLASH  ----------->   DAEWOO L32S635VKE, Main: MSD3463-T4C1, Panel: K320WD82


 The appearance of the MainBoard MSD3463-T4C1 is shown in the figure below:
MSD3463-T4C1
Main features of the DAEWOO L32S635VKE device:
Installed matrix (LED-panel) K320WD82 or LC320DXY (SH) (A4).
To power the backlight LEDs, a converter is used, combined with the main board MSD3463-T4C1, controlled by the OB3350CP PWM controller. As power elements of the LED driver, keys of the AOD4286 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using LNK6777 microcircuits.
MainBoard - the main board (motherboard) is an MSD3463-T4C1 module using SPI Flash chips: MX25L6406E, Audio: TPA3110LD2 and others.
The ST43WS-2A-E tuner provides TV reception and channel tuning.

 Brand: DAEWOO, Model: L32S635VKE.
Briefly from the TV: LCD, LED backlight, 32 ", 1366x768, 720p HD, TFT IPS, DVR, sound: 12 W, HDMI connectors: 2.
The composition uses MainBoard MSD3463-T4C1 and an LCD panel (matrix) K320WD82. The power supply is combined with the MainBoard.
Technical description
DAEWOO L32S635VKE LED TV with K320WD82 LCD display, 32 "(81 cm) diagonal size 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 high-quality HD images with a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready) Supported media file formats: MP3, MPEG4, DivX, MKV, JPEG.
The power of the sound system 12 W (2x6 W) provides 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 x2, USB. An output for connecting headphones is provided. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with stand 730x479x200 mm, without stand 730x420x90 mm.
TV Weight: 4 kg.
Attention! The K320WD82 panel of a DAEWOO L32S635VKE LED TV 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.