Saturday, 4 April 2020

REPAIR / SERVICING TV TOSHIBA 50L4353RK

Technical description and composition of the TOSHIBA 50L4353RK TV, type of panel and applicable modules. The composition of the modules.
TOSHIBA LED
Model: 50L4353RK
Chassis / Version: 32L4300
Panel: LC500DUE (SF) (R1)
LED backlight: 50 R0W2.1 Rev0.4 1 - 6916L-1273A, 6916L-1276A, 6916L-1241A, 6916L-1272A
T-CON: 6870C-0452A, LC500DUE-SFR1
LED driver (backlight): integrated into PSU; 111V 800mA
Power Supply (PSU): B191-002 4H.B1910.001 DARFON D1, B191-002 D25 0433-0082000
MainBoard: 32L4300 REV1.02 60EB40M1MB01P
IC MainBoard: CPU: MSD8881CV-W9N; DRAM: H5TQ2G63DFR; NAND Flash: THGBM4G4D1HBAIR; SPI Flash: W25Q16CVSSIG
Tuner: TDSS-G231D
Control: Remote: CT-90429, IR: LV2-IR SFIS, Wi-Fi: 1353A-WLU5053 WLU5053 D4
Specifications 50L4353
TOSHIBA 50L4353RK
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The TOSHIBA 50L4353RK TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
In such cases, the B191-002 power supply is usually faulty. 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 breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually 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), in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
In most of these cases, a malfunction is detected in the nodes and backlight elements of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters, as a rule, light up a single 3-volt LED in the forward direction. In the case of using dual 6-volt LEDs, the PN junction of its protective zener diode can serve as a health indicator. In faulty LEDs, the zener diode will either be cut off or broken into short-circuit.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the 32L4300 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). Sometimes they require checking or replacing (if necessary) the elements of the MainBoard - CPU board: MSD8881CV-W9N; DRAM: H5TQ2G63DFR; NAND Flash: THGBM4G4D1HBAIR; SPI Flash: W25Q16CVSSIG. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
The TDSS-G231D tuner malfunction 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! For users and owners of 50L4353RK TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-serviceability of the device.


Service Manuals with Schematic Diagrams 110 pages of 2013 on models ------>  32L4332, 32L4333, 39L4333, 50L4333, 32L4353, 39L4353, 50L4353, 32L4363, 39L4363, 50L4363, 40L6353, 50L6353, 40L6363, 50L6363, 40L7333, 50L7333, 58L7333, 40L7353, 50L7353, 58L7353, 40L7363, 50L7363, 58L7363


The appearance of the MainBoard 32L4300 is shown in the figure below:
32L4300
32L4300 can be used in TVs:
TOSHIBA 32L4353RB (Panel T320HVN04), TOSHIBA 39L4353RB (Panel T390HVN01.0 / XL), TOSHIBA 40L6353RK (Panel LSC400HM06 T01), TOSHIBA 40L7356RK (Panel LSC400HF03 T01), TOSHIBA 40L7363RK (Panel LSC400HF03 T01), TOSHIBA 50L7363RK (Panel 50 inch), TOSHIBA 32L6353RK (Panel 96.32S14.001), TOSHIBA 39L4363D (Panel T390HVN01.0 XL), TOSHIBA 50L4353RK (Panel LC500DUE (SF)(R1)).
The appearance of the power supply
Main features of the TOSHIBA 50L4353RK device:
Installed matrix (LED-panel) LC500DUE (SF) (R1).
The matrix control uses the Timing Controller (T-CON) 6870C-0452A.
To power the backlight LEDs, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the TOSHIBA 50L4353RK TV is carried out by the power module B191-002, or its analogs.
MainBoard - the main board (motherboard) is a 32L4300 module using CPU chips: MSD8881CV-W9N; DRAM: H5TQ2G63DFR; NAND Flash: THGBM4G4D1HBAIR; SPI Flash: W25Q16CVSSIG and others.
The TDSS-G231D tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC500DUE-SFR1
Type: a-Si TFT-LCD, Panel
Diagonal size: 50 inch
Resolution: 1920x1080, FHD
Display Mode: IPS, Normally Black, Transmissive
Active Area: 1095.84x616.41 mm
Surface: Antiglare (Haze 1%), Hard coating (3H)
Brightness: 300 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Without Driver
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V

Trademark: TOSHIBA, Model: 50L4353.
Briefly from the TV: LCD, LED backlight, 50 ", 1920x1080, 1080p Full HD, DVR, sound: 14W, HDMI connectors: 4, Internet access, Wi-Fi, Smart TV.
For the 50L4353DB model, the official website has firmware (software update) version 7.1.92.43.01.1.
The composition includes MainBoard 32L4300 REV1.02 60EB40M1MB01P and LCD panel (matrix) LC500DUE (SF) (R1).
Power Supply Unit (PSU) B191-002 4H.B1910.001, 0433-0082000 Power Supply.
Technical description
TOSHIBA 50L4353 LED TV with LC500DUE LCD display, diagonal size 50 "(127 cm) in 16: 9 format. The required screen brightness of 300 cd / m² is provided by LED backlighting. LED display technology is implemented in this model's display technology. Design and the technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in the graphic resolution of the standard 1080p (Full HD).
The 50L4353 is equipped with SMART software, integrated applications and the ability to work on the Internet. Connecting to the Internet can be done via Wi-Fi. The input high-frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, Xvid, DivX, MKV, JPEG.
The power of the speaker system of sound 14 W (2x7 W) provide two speakers. The audio processing system NICAM STEREO is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, RGB, VGA, HDMI x4, MHL, USB x2, Ethernet (RJ-45), Wi-Fi, WiDi, Miracast. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
The power consumed by the TV in the operating mode from the network is 177 watts.
Overall dimensions: with stand 1136x743x230 mm, without stand 1136x669x84 mm.
TV Weight: with stand: 18 kg, without stand: 16.2 kg.
Attention! The TOSHIBA 50L4353 LED TV panel LC500DUE (SF) (R1) 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.