Technical description and composition of the TOSHIBA 42SL738R TV, panel type and applicable modules. The composition of the modules.TOSHIBA LED
Model: 42SL738R
Panel: LC420EUD (SC) (A2)
T-CON: 6870C-0319B R8J010,
LED driver (backlight): 6917L-0022B
PWM LED driver: AS3693B, BA9743A (16)
MOSFET LED driver: AOB414
Power Supply (PSU): 715G4307-P02-H20-003U 42SL700A, ADTVA2416AAB
PWM Power: A6069H (7),
MainBoard: 715G4357 - M01-000-005X
IC MainBoard: NAND Flash: HY27US08281A; EEPROM: 24c32;
Tuner: ENV57S01D8RF
Control: CT-90326
Specifications 42SL738
TOSHIBA 42SL738R
General repair guidelines for TV LCD LED
Repair of the TOSHIBA 42SL738R TV should begin with a careful external examination of all its components and modules. Visible damage to elements can sometimes indicate the direction of the search for a defect even before the necessary measurements are taken. In most cases, the repairman can guess the causes of the defect and possible consequences from the characteristic signs of typical TV defects, for example, ring cracks formed in the soldering of the element leads, swollen rectifier filter capacitors, charred resistors and other circuit elements.
Sometimes the TOSHIBA 42SL738R TV simply does not turn on. No control lights on the front panel are lit or blinking, the TV does not respond to the remote control and does not make any sounds or any signs of life when turned on. The most likely cause of the malfunction is a failure of the general power module 715G4307-P02-H20-003U 42SL700A, ADTVA2416AAB. If it is working properly, you need to check the processor batteries on the SSB (Main Board). When diagnosing and repairing the power supply, first of all, replace the swollen capacitors of the filter of the secondary rectifiers and check the fuse and, if it is broken, it is necessary to identify the cause. Often in such cases, an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module — rectifier diodes and transistors in the primary circuit.
The reasons for the breakdown of the power switch in switching power supplies (IIPS) can be different, for example, a malfunction of semiconductor elements or electrolytic capacitors in the stabilization circuits of the primary circuit, as well as a failure in the operation of the A6069H PWM controller chip (7), or broken resistors in its bundle .
If, when you turn on the TV, the image appears and immediately disappears, or is missing initially when you turn 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 LC420EUD-SCA2 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.
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.
If the motherboard CBPFA4ARA5 100Hz 715G4318-T01-000-005B MT8282AGG is faulty, first of all it is necessary to check all the linear stabilizers or power converters of its chips, and also, if necessary, update the software. Sometimes you can check the health of MB only by replacement.
If there is no reception of television channels, but the TV is working properly from external devices, first of all it is necessary to check the voltage of the varicap tuner ENV57S01D8RF, which is usually within 30-33V, as well as other supply voltages on the terminals of the tuner.
Attention! For users and owners of 42SL738R 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.
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 26/32/42SL738G
The appearance of the MainBoard 715G4357 is shown in the figure below:715G4357
715G4357 can be used in TVs:
TOSHIBA 26SL738R (Panel LC260EXN-SCA1), TOSHIBA 32SL738R (Panel LC320EXN (SC)(A2) LED), TOSHIBA 42SL738R (Panel LC420EUD (SC)(A2)).
Key Features of the TOSHIBA 42SL738R:
Installed matrix (LED-panel) LC420EUD (SC) (A2).
The matrix control uses the Timing Controller (T-CON) 6870C-0319B.
The LED driver 6917L-0022B is used to power the backlight LEDs, it is controlled by the AS3693B, BA9743A PWM controller (16). As the power elements of the LED driver, keys of the AOB414 type are used.
The necessary supply voltages for all nodes of the TOSHIBA 42SL738R TV are generated by the 715G4307-P02-H20-003U power module, or its analogs using A6069H microcircuits (7) ,.
MainBoard - the main board (motherboard) is a 715G4357 module using NAND Flash chips: HY27US08281A; EEPROM: 24c32; and others.
The ENV57S01D8RF tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC420EUD-SCA2
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare, Hard coating (3H), Reflection 2.0% (Max.)
Brightness: 450 cd / m²
Contrast Ratio: 1300: 1
Display Colors: 16.7M / 1.06B (8-bit / 8-bit + Dithering), CIE1931 72%
Response Time: 5 (Typ) (G to G); 8 (MPRT)
Frequency: 120Hz + 120Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (4 ch, 10-bit), 92 pins
Voltage: 12.0V
Trademark: TOSHIBA, Model: 42SL738.
Briefly from the TV: LCD, LED backlight, 42 ", 1920x1080, 1080p Full HD, sound: 20W, HDMI: 4.
The Toshiba official website has firmware (software update) for models 42SL738R (2.04), 42SL738N (2.04), 42SL738G (2.04), 42SL738F (2.04).
The composition uses MainBoard 715G4357-M01-000-005X and LCD panel (matrix) LC420EUD (SC) (A2).
Power Supply Unit (PSU) 715G4307-P02-H20-003U, ADTVA2416AAB Power Supply.
TOSHIBA 42SL738 LED TV with LC420EUD LCD, 42 "(107 cm) diagonal size in 16: 9 format. The required screen brightness of 450 cd / m² is provided by LED backlighting. The ratio of maximum brightness to minimum (contrast) is 1300: 1 Dynamic contrast ratio of 1,000,000: 1 is achieved by special control of the LEDs. This model uses a side illumination of Edge LEDs. The design and technical capabilities of the TV include viewing programs and movies in high quality HD with a resolution of 1920x1080 pixels it is in a graphic decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p Supported media file formats: MP3, JPEG.
The power of the sound system 20 W (2x10 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, component, SCART x2, RGB, VGA, HDMI x4, 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 101 watts.
Overall dimensions: with stand 1005x669x249 mm, without stand 1005x622x37 mm.
TV Weight: with stand: 19.6 kg, without stand: 17.3 kg.
Attention! The TOSHIBA 42SL738 LED TV panel LC420EUD (SC) (A2) 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.