Saturday 2 May 2020

REPAIR / SERVICING TV MYSTERY MTV-3212W

Technical description and composition of the MYSTERY MTV-3212W TV, panel type and applicable modules. The composition of the modules.
MYSTERY
Model: MTV-3212W
Chassis / Version: V1L12
Panel: LVW320CSOT C1
T-CON: ST3151A04-1
Inverter (backlight): integrated into PSU
PWM Inverter: MP1006
MOSFET Inverter: FQPF5N60C
Power Supply (PSU): PL3202A
PWM Power: FAN7930 (PFC), LD7536
MOSFET Power: 12A50D, 6A60D
MainBoard: 40-OMS82D-MAD2LG
IC MainBoard: Spi Flash: W25Q32BV, Sound: MSH9010-LF
Tuner: XF-3SA
Control: IR: 40-L32R28-IRB2XG
Technical Specifications MTV-3212W
MYSTERY MTV-3212W
General recommendations for repairing TV LCD
Possible malfunctions
- The MYSTERY MTV-3212W TV does not turn on, does not respond to the remote control and the control panel buttons, does not blink with any indicators.
With such manifestations, a malfunction is most likely to be detected in the PL3202A power supply module. It is then necessary to measure its output voltages and, if they are absent, you should check the power switches (12A50D, 6A60d) and rectifier diodes of the converters for a short circuit probability.
In case of diode breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key 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 the excess of maximum current or voltage values. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power switch may be PWM (PWM) FAN7930 (PFC), LD7536. It is checked only by replacement with a known good one.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or the inverter.After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, you must ring in its converter power keys for breakdown and secondary windings of transformers for an open.
Sometimes, for diagnostic purposes, inverter protection must be disabled. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the 40-OMS82D-MAD2LG 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). Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - Spi Flash: W25Q32BV, Sound: MSH9010-LF and failed chips, replace them with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
Before changing the XF-3SA tuner, if there is no possibility of tuning to television channels, you should make sure that there are supply voltages that must be measured at the corresponding tuner pins and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention! Users and owners of MTV-3212W TVs who do not have the appropriate qualifications, knowledge and experience are strongly advised against self-repair attempts in order to avoid negative consequences that could lead to complete non-repairability of the device.

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    PL3202A Power supply

FIRMWARE FOR SPI FLASH  ----------->   MYSTERY MTV-3212W V1L12, Main: 40-OMS82D-MAD2LG, Panel: LVW320CSOT C1

 The appearance of the MainBoard 40-OMS82D-MAD2LG is shown in the figure below:
40-OMS82D-MAD2LG
40-OMS82D-MAD2LG can be used in TVs:
MYSTERY MTV-2419LW (Panel LC230EUE (SE)(A1) ), MYSTERY MTV-3212W (Panel LVW320CSOT C1).
The appearance of the power supply
Main features of the MYSTERY MTV-3212W device:
Installed matrix (LCD panel) LVW320CSOT C1.
The matrix control uses the Timing Controller (T-CON) ST3151A04-1.
To power the backlight, a converter is used, combined with the power supply, controlled by the MP1006 PWM controller. As power elements of the inverter, keys of the type FQPF5N60C are used.
The required supply voltages for all nodes of the MYSTERY MTV-3212W TV are generated by the PL3202A power supply module or its analogs using FAN7930 (PFC), LD7536 microchips and 12A50D, 6A60D power switches.
MainBoard - the main board (motherboard) is a 40-OMS82D-MAD2LG module, using Spi Flash chips: W25Q32BV, Sound: MSH9010-LF and others.
The XF-3SA tuner provides TV reception and channel tuning.
MYSTERY MTV-3212W TV with LVW320CSOT LCD display, 32 "(81 cm) diagonal size in 16: 9 format. Screen brightness of 300 cd / m² is ensured by backlighting with CCFL (EEFL) fluorescent lamps. Contrast, as the ratio of maximum brightness to minimum, is 4000: 1. It is possible to 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 processing and digital signal generation takes place in st . Ndartah 480i, 480p, 576i, 576p, 720p, 1080i Supported multimedia file formats: MP3, WMA, MPEG4, Xvid, MKV, JPEG.
The power of the sound system 10 W (2x5 W) provides 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, VGA, HDMI, USB. 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, 1360x768.
The power consumed by the TV in the operating mode from the network is 80 watts.
Dimensions: With stand 642x444x209 mm, Without stand 570x345x70 mm.
Attention! The LVW320CSOT C1 panel of the MYSTERY MTV-3212W LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!