Friday, 1 May 2020

REPAIR / SERVICING TV MYSTERY MTV-4029LTA2

Technical description and composition of the MYSTERY MTV-4029LTA2 TV, panel type and applicable modules. The composition of the modules.
MYSTERY LED
Model: MTV-4029LTA2
Chassis / Version: V2N03
Panel: V390HJ1-P02
T-CON: V390HJ1-XC01
LED driver (backlight): integrated into PSU
PWM LED driver: OB2263, AP3616M28-G1
MOSFET LED driver: MDF0765 (7A 600V)
Power Supply (PSU): TV4205-ZC02-01
PWM Power: FAN7930 (PFC), OB2273
MOSFET Power: FDPF18N50
MainBoard: MSDV3224-ZC01-01 & HS1 IP2000-ZC01-01 & MSAV3220ZC26-02
IC MainBoard: MSD308BT-SW, TPA3113D2, 25Q64BS, K4B1G1646G-BCKO, NT5CB128M16HP-D
Technical Specifications MTV-4029LTA2
MYSTERY MTV-4029LTA2
General repair guidelines for TV LCD LED
A malfunction of the power supply is often manifested corny - the TV does not turn on, does not make any sounds, does not light up and does not blink with any indicators. It is advisable to start the troubleshooting of the power supply module by checking the state of the electrolytic capacitors of the rectifier filters and the mains fuse. Defective capacitors should be replaced. If the mains fuse is broken, it is necessary to check first of all the power semiconductor elements - rectifier diodes and transistors, which are often found in such a state of breakdown.
It should be remembered that in the practice of repair, usually the power switches in switching power supplies (SMPS) do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the OB2263, OB2273 PWM controller chip itself may be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
If the MYSTERY MTV-4029LTA2 has no image, there is sound and the channels are switched, there is a possibility of a malfunction in the backlight LED circuit of the V390HJ1 panel, or their power converter - LED driver. Sometimes, when turned on, the image appears and immediately disappears. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the backlight unit.
A malfunction in the backlight circuits often occurs due to an open in the power circuit of the LED lines. It requires disassembling the panel and checking the LEDs themselves, the rations of their terminals, as well as the reliability of the connections in the connectors and rations of the terminals.
It is impossible to check the line of series-connected LEDs without a special current source, and for this purpose it is not safe to use any voltage sources above 12V for them. Then it remains only to open the panel and check each LED separately. Usually, Chinese 9V-powered multimeters light up a single 3-volt LED, if you connect the probes in the forward direction, the red probe to the anode, and the black to the cathode. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
In cases of attempts to repair the motherboard MSDV3224-ZC01-01 + HS1 IP2000-ZC01-01 + MSAV3220ZC26-02, it is necessary to check the operability of the linear stabilizers and power converters of its microcircuits and, if possible, update the software (software). BGA chips can sometimes be diagnosed with local heating.
In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - MSD308BT-SW, TPA3113D2, 25Q64BS, K4B1G1646G-BCKO, NT5CB128M16HP-D with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.

It should be remembered! Attempts to repair the TV MYSTERY MTV-4029LTA2, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete failure of the device!


SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    TV4205-ZC02-01 Schematic diagram

FIRMWARE FOR SPI FLASH  ----------->   MYSTERY MTV-4029LTA2 V2N03, Main: MSDV3224-ZC01-01, Panel: V390HJ1-P02



To reduce the backlight current in LED drivers with the AP3616M28-G1 terminal stage, the total resistance of the resistors from terminal 22 (ISET AP3616M28) to the housing should be proportionally increased. The maximum current in each of the 16 channels is 75 mA. To increase the current in the diodes, the channels are connected in parallel. The current in milliamperes in each channel is determined from the calculation of 1560 * 1.194 / Rset, where Rset is the resistance from the ISET output to the housing in kilo-ohms.

Repair MainBoard
The appearance of the MainBoard MSDV3224-ZC01-01 is shown in the figure below:
MSDV3224-ZC01-01
MSDV3224-ZC01-01 can be used in TVs:
MYSTERY MTV-4029LTA2 (Panel V390HJ1-P02), MYSTERY MTV-4128LTA2 (Panel LSC400HN01-G01).
PSU Advanced
The TV4205-ZC02-01 power supply module is made using the Power Factor Correction (PFC) scheme to eliminate multiple AC harmonics introduced into the power supply by the device. The PFC node is a Step-Up Converter based on the FAN7930 PWM controller, which evenly distributes high-frequency pulses of the charging current of the electrolytic capacitor of the rectifier filter of the mains voltage over a period of 50 Hz. The current of its charge in this case will already be determined not by its reactance (usually 10-30 ohms for the network frequency), but by the elements of the converter. As a result, a change in the amplitude of the pulses (envelope) of the consumed current of the converter will repeat the shape and phase of the input sinusoidal voltage. The availability of an increased voltage (about + 380V) in the operating mode on the capacitor of the line filter indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the MYSTERY MTV-4029LTA2 device:
Installed matrix (LED panel) V390HJ1-P02.
The matrix control uses the Timing Controller (T-CON) V390HJ1-XC01.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the OB2263 PWM controller, AP3616M28-G1. As power elements of the LED driver, keys of the type MDF0765 (7A 600V) are used.
The required supply voltages for all nodes of the MYSTERY MTV-4029LTA2 television are generated by the TV4205-ZC02-01 power supply module or its analogs using FAN7930 (PFC), OB2273 microcircuits, and FDPF18N50 type power switches.
MainBoard - the main board (motherboard) is an MSDV3224-ZC01-01 module, using microcircuits MSD308BT-SW, TPA3113D2, 25Q64BS, K4B1G1646G-BCKO, NT5CB128M16HP-D and others.
Additional technical information about the panel:
Brand: CHIMEI INNOLUX
Model: V390HJ1-P02
Type: a-Si TFT-LCD, CELL
Diagonal size: 39 inch
Resolution: 1920x1080, FHD
Display Mode: MVA, Normally Black, Transmissive
Active Area: 853.92x480.33 mm
Surface: Antiglare (Haze 3.5%), Hard coating (3H)
Glass Depth: 0.50 + 0.50 mm
Transmissivity: 5.8% (with Polarizer)
Contrast Ratio: 3000: 1
Display Colors: 16.7M (8-bit)
Response Time: 8.5 (G to G)
Frequency: 60Hz
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
MYSTERY MTV-4029LTA2 TV with V390HJ1-P02 LCD, 40 "(102 cm) diagonal size of 16: 9 format. The required screen brightness of 250 cd / m² is provided by LED backlighting. Contrast, as the ratio of maximum brightness to minimum, is 1000: 1. Edge LED backlighting is implemented in the LED-panel of this TV - Edge LED.The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphical decomposition according to the standard 1080p (Full HD).
MTV-4029LTA2 TV has built-in SMART Software and pre-installed Android Operating System. 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, MPEG4, DivX, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by 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, VGA, HDMI x2, USB, Ethernet (RJ-45), Wi-Fi. 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, 1360x768, 1920x1080.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Dimensions: With stand 642x444x209 mm, Without stand 570x345x70 mm.
Attention! The V390HJ1-P02 panel of the MYSTERY MTV-4029LTA2 LED TV is an expensive and unreliable element.