Thursday, 2 April 2020

REPAIR / SERVICING TV TOSHIBA 32KL933R

Technical description and composition of the TOSHIBA 32KL933R TV, type of panel and applicable modules. The composition of the modules.
TOSHIBA LED
Model: 32KL933R
Chassis / Version: 17MB62
Panel: LTA320AN12 T01
T-CON: A320AN12S4LV0.0
LED driver (backlight): SSL320 0E1A Rev1.1
Power Supply (PSU): 17IPS19-3
PWM Power: SG6742HR (8 pin), ICE3BR0665J (Standby)
MOSFET Power: FQPFN50C
MainBoard: 17MB62-2.5
Tuner: SUT-RE216TN
Control: CT-8023
Specifications 32KL933
TOSHIBA 32KL933R
General repair guidelines for TV LCD LED
Repair of the TOSHIBA 32KL933R TV should begin with a fault diagnosis, which involves a careful examination of the external and internal elements of the device. Often, based on certain external signs, it may be possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. If charred resistors, swollen electrolytic or cermet capacitors, ring cracks in the solders of the terminals of transformers or heating elements are found, it is advisable to establish the causes and consequences of the malfunction that has arisen, as well as to check the connected elements and assemblies.
If the TOSHIBA 32KL933R does not turn on, no control lights on the front panel light up or blink; therefore, there is a very high probability of a 17IPS19-3 power supply module malfunctioning. In some cases, only the processor power regulator may be faulty. In the absence of swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply should be started by checking the fuse and, if it is broken, it is first necessary to check all the power semiconductor elements of the primary circuit - diodes and transistors for the possibility of an avalanche or thermal breakdown.
It should be borne in mind that in the practice of repair it is extremely rare that key transistors in switching power supplies (SMPS) fail for no reason that should be sought by checking other components, for example, a breakdown of the key can provoke faulty elements of the damper circuits, or dried electrolytic capacitors or dangling primary resistors BP circuits involved in the stabilization process. In this case, all semiconductor elements of the strapping of the ICE3BR0665J PWM controller microcircuit (8) are subject to verification, which it is desirable to verify by replacement.
If, when you turn on the TV, the image appears and immediately disappears, or is initially absent when turned on, but the sound has other functions that work, there is a high probability of a malfunction of the LED driver (power converter for the backlight LEDs of the LTA320AN12 T01 panel). In such cases, the general power module is also subject to verification, in which the electrolytic capacitors of the rectifier filter supplying the LED driver should be checked.
To check the health of the LEDs, as well as contact connections in the ruler circuit, it is necessary to disassemble the panel.
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.
Diagnostics and repair of the 17MB62-2.5 motherboard is carried out by checking the operability of the stabilizers or power converters of the module chips. In some cases, a software update is required.
If the TV works normally from external devices, but does not tune into television channels, the SUT-RE216TN tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals, as well as the power supply of varicaps (30-33V).
Attention to the owners! Attempts to repair the TOSHIBA 32KL933R TV independently are not recommended by the manufacturer and can lead to serious negative consequences!

 SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    Vestel Main 17MB62-2.

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    17IPS19-4 Power Supply Schematic Diagram


 Software update 32KL933R (0.6.8c) can be downloaded here


 The appearance of the MainBoard 17MB62-2.5 is shown in the figure below:
The 17MB62-2.5 motherboard is made using the MSD9WB9PT-2 processor, combined with a scaler. For its operation, random-access memory (DDR) K4T1G164QF, or HY5PS121621C, and NAND512-A read-only memory (ROM) are used. To ensure processor power, DC / DC converters with output voltages of 1.2V, 2.5V, 3.3V are used. For DDR, the voltage is 1.8V, for NAND it is either 1.8 or 3.3V. It is advisable to start the repair by checking the supply voltage in stand-by mode (12V), 5V and 3.3V. Further, in the operating mode, it is necessary to check the operability of all linear stabilizers and DC / DC voltage converters used to power the MB and LCD panel chips. If there is a backlight and no image, depending on the type of panel used, its 5V or 12V power supply can be measured directly on the LVDS connector.
A typical malfunction of this board is a NAND software failure. At the same time, the TV does not turn on and blinks alternately with indicators on the panel. If the software of the SPI FLASH chip, in which the bootloader is located, is not damaged, NAND is updated via the USB port with standard software. Otherwise, it makes sense to try downloading the software if there is a mboot.bin file on the media, which can be used as standard SPI FLASH content.
17MB62-2.5 can be used in TVs:
TOSHIBA 19KL933R (Panel LTA185AT01), TOSHIBA 32KL933R (Panel LTA320AN12 T01), TOSHIBA 26KL933R (Panel LC260EXN (SD)(A3)), TOSHIBA 23KL933R (Panel LTM230HT10).
PSU Advanced
The 17IPS19-3 power supply module is made using the Power Factor Correction (PFC) scheme to filter the higher harmonics of the alternating current introduced by the device into the mains. The PFC node is a Step-Up Converter based on the ICE3BR0665J PWM controller, which evenly distributes high-frequency pulses of the charge current of the electrolytic capacitor of the rectifier filter of the left voltage evenly over a period of 50 Hz. As a result, the change in the amplitude of the pulses (envelope) of the consumed current repeats a sinusoidal shape.
The appearance of the power supply
Key Features of the TOSHIBA 32KL933R:
Installed matrix (LED-panel) LTA320AN12 T01.
The matrix control uses the Timing Controller (T-CON) A320AN12S4LV0.0.
The LED driver SSL320 is used to power the backlight LEDs.
The necessary supply voltages for all nodes of the TOSHIBA 32KL933R TV are generated by the 17IPS19-3 power supply module or its analogs using SG6742HR (8 pin), ICE3BR0665J (Standby) microcircuits and power switches of the FQPFN50C type.
MainBoard - the main board (motherboard) is a 17MB62-2.5 module.
The SUT-RE216TN tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA320AN12
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: PVA, Normally Black, Transmissive
Active Area: 697.685x392.256 mm
Surface: Antiglare, Hard coating
Brightness: 320 cd / m²
Contrast Ratio: 4000: 1
Display Colors: 16.7M (8-bit), CIE1931 70%
Response Time: 20 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V

 TOSHIBA 32KL933 LED TV with LTA320AN12 LCD, 32 "(81 cm) diagonal size in 16: 9 format. The required screen brightness of 300 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 3000000: 1 is achieved by special control of the LEDs. V This model uses side illumination from Edge LEDs. You can view images in high quality HD at a resolution of 1366x768 pixels in the standard for graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NT SC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, MPEG4, DivX, MKV, VideoCD, SVCD, Picture CD, JPEG.
The power of the speaker system of sound 5 W (2x2.5 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, SCART, RGB, VGA, HDMI x2, USB. 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 standards.
The power consumed by the TV in the operating mode from the network is 135 watts.
Overall dimensions: with stand 770x528x191 mm, without stand 770x483x64 mm.
TV Weight: with stand: 10 kg, without stand: 8.8 kg.
Attention! The LTA320AN12 T01 panel of the TOSHIBA 32KL933 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.