Tuesday, 31 March 2020

REPAIR / SERVICING TV TOSHIBA 19EL833R

Technical description and composition of the TOSHIBA 19EL833R TV, type of panel and applicable modules. The composition of the modules.
TOSHIBA LED
Model: 19EL833R
Chassis / Version: 17MB60 VESTEL
Panel: V185B1-LE2 LED
LED driver (backlight): 17CON07-2 VESTEL
PWM LED driver: 3389DR
Power Supply (PSU): 17PW05-3 VESTEL
PWM Power: ICE3BR0665J (Standby)
MainBoard: 17MB60-4
IC MainBoard: MSD9WB9PX-LF-2, MX25L8005, W971GG6JB-18, K9F1208UOC, TPA3113, DTOS403LH122E
Tuner: DTDS403LH122E
Control: CT-90326
Specifications 19EL833
TOSHIBA 19EL833R
General repair guidelines for TV LCD LED
Repair of electronic equipment usually begins with its external inspection and diagnosis of the malfunction. In this case, you should examine all the internal components of the TOSHIBA 19EL833R TV, as well as the external elements of the housing. Many visible changes in the state of the elements make it possible to determine the further direction of troubleshooting and localization of the defect. If ring cracks are detected in the soldering of the terminals of the elements or dangling connecting tracks, swollen capacitors or charred resistors - all this can be characteristic signs of the causes or consequences of an already known typical malfunction.
In the case when the 19EL833R does not turn on, does not respond to the remote control and buttons on the front panel, does not blink bulbs and does not show any signs of operability, the power supply module 17PW05-3 VESTEL is probably faulty in this case. If it is serviceable under such manifestations, it is necessary to check the power supply stabilizer (converter) of the processor on the motherboard.When diagnosing and repairing the power supply, after replacing the swollen capacitors of the secondary rectifier filters (if any), you must first check the mains fuse. When it is broken, the power elements of transistors and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
The reasons for the breakdown of the power switch in switching power supplies (IIPS) can be different, for example, a malfunction of semiconductor cells or electrolytic capacitors in the stabilization circuits of the primary circuit, as well as a failure in the operation of the PWM controller chip 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 V185B1-LE2 LED 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.
A break in the line of LEDs connected in series cannot be detected with a multimeter or tester without disassembling the panel. To open all the transitions, several tens of volts are needed, and it is best to use a current source for such purposes.
On the 17MB60-4 motherboard, in case of a malfunction, you should first check the performance of all the stabilizers or power converters of the microcircuits and, if necessary, update the software (software).
Before changing the tuner tun DTDS403LH12, if it is not possible to tune to television channels, make sure that there are supply voltages, including varicap power (30-33V), which must be measured on the corresponding tuner pins.
Remember! Attempts to self-repair by users of the TOSHIBA 19EL833R TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    TOSHIBA 19DL833R, 19DL834R, 19EL834R. Main VESTEL 17MB60



 The appearance of the MainBoard 17MB60-4 is shown in the figure below:
The 17MB60-4 motherboard is made using the MSD9WB7PX-2 processor, combined with a scaler. For its work, two microchips of external random access memory (DDR) HY5PS121621C and read-only memory (ROM) NAND512-A are used. To ensure processor power, stabilizers 1.2V, 2.5V, 3.3V are used. For DDR, the voltage is 1.8V, for the power of NAND 3.3V. It is advisable to start the repair by checking the power supply of the standby mode 3.3V. Further in the operating mode, it is necessary to check the operability of all linear voltage stabilizers and converters. If there is a backlight and no image, the power of the LCD panel 5V or 12V, depending on the type of panel used, can be measured directly on the LVDS connector. A typical malfunction is a NAND ROM software failure. At the same time, the TV does not turn on and the indicators on the panel blink. It is updated via the USB port if the software of the SPI FLASH chip in which the bootloader is located is not damaged, or if there is a mboot.bin file on the media, which can be used as standard SPI FLASH content.
17MB60-4 can be used in TVs:
SHARP LC-19LE510RU (Panel LC185EXN (SD)(A1)), SHARP LC-22LE510RU (Panel 22 "), SHARP LC-32LE510RU (Panel LC320EUN SD V1), SHARP LC-32SH130E (Panel LC320WXN / 720p HD), SHARP LC-32SH340 LC-32SH340E (Panel LC320WUN (SC)(B1) ), TOSHIBA 19EL833R (Panel V185B1-LE2 LED), TOSHIBA 26LD833F (Panel LC260EXN (SD)(A3)), TOSHIBA 32DL833R 32DL834R (Panel LC320EXN SD A2 led).
The appearance of the power supply
Main features of the TOSHIBA 19EL833R device:
Installed matrix (LED panel) V185B1-LE2 LED.
The LED driver 17CON07-2 is used to power the backlight LEDs, it is controlled by the 3389DR PWM controller.
The necessary supply voltages for all nodes of the TOSHIBA 19EL833R TV are generated by the 17PW05-3 power supply module or its analogs using ICE3BR0665J (Standby) microcircuits.
MainBoard - the main board (motherboard) is a 17MB60-4 module, using microchips MSD9WB9PX-LF-2, MX25L8005, W971GG6JB-18, K9F1208UOC, TPA3113, DTOS403LH122E and others.
The DTDS403LH122E tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CHIMEI INNOLUX
Model: V185B1-LE2
Type: a-Si TFT-LCD, Panel
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit), CIE1931 70%
Response Time: 1.3 / 3.7 (Tr / Td)
Frequency: 60Hz
Lamp Type: 14S8P WLED Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V
 Trademark: TOSHIBA, Model: 19EL833.
Briefly from the TV: LCD, LED backlight, 19 ", 1366x768, 720p HD, sound: 5W, HDMI connectors: 2.
The composition uses MainBoard 17MB60-4 and the LCD panel (matrix) V185B1-LE2.
Power Supply Unit (PSU) 17PW05-3 VESTEL Power Supply.
TOSHIBA 19EL833 LED TV with V185B1-LE2 LCD, 19 "(48 cm) diagonal, 16: 9 format. The required screen brightness of 250 cd / m² is provided by LED backlighting. The ratio of maximum brightness to minimum (contrast) is 1000 : 1. 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, NTSC Graphic th processing and the formation of the digital signal is in 480i standards, 480p, 576i, 576p, 720p, 1080i, 1080p Supported multimedia file formats:. MP3, WMA, MPEG4, Xvid, MKV, JPEG.
The power of the speaker system of sound 5 W (2x2.5 W) provide 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, 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.
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 40 watts.
Overall dimensions: with stand 462x376x159 mm, without stand 462x302x35 mm.
TV mass: with stand: 4 kg, without stand: 3.4 kg.
Attention! The V185B1-LE2 panel of the TOSHIBA 19EL833 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.