Tuesday, 28 April 2020

REPAIR / SERVICING TV MYSTERY MTV-1911WL

Technical description and composition of the MYSTERY MTV-1911WL TV, type of panel and applicable modules. The composition of the modules.
MYSTERY LED
Model: MTV-1911WL
Chassis / Version: MSTV2407-ZC01-01
Panel: V185B1-L15 REV.C1
LED driver (backlight): integrated into MainBoard
PWM LED driver: AP3039AM, AP3608EM-G1
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6 OB2273
MainBoard: MSTV2407-ZC01-01
IC MainBoard: Cpu: MST6E181VS-LF-Z1, Spi Flash: MX25L3206E, Eeprom: 24C16
Tuner: F35WT-2A-E
Appearance
MYSTERY MTV-1911WL
General repair guidelines for TV LCD LED
Repair of the MYSTERY MTV-1911WL TV should begin with a careful external examination of all its components and modules. According to some external signs of a change in the state of some elements, it is sometimes possible to make assumptions about the nature of the defect, as well as determine the further direction of the troubleshooting. Swollen electrolytic or cermet capacitors, charred resistors, ring cracks in the soldered terminals of the elements - all this can significantly help the master to determine the causes and consequences of the malfunction of the TV.
In the absence of any signs of operability, when the MYSTERY MTV-1911WL does not turn on and does not signal anything with the control lights on the panel, there is a possibility of a malfunction of the TV power module. After checking the mains fuse and power elements of the primary power supply circuit, it should also check the absence of a short circuit in the loads of the secondary rectifiers.
In most cases, key breakdowns in switching power supplies (SMPS) do not occur for no reason and you should look for other faulty circuit elements that could provoke a defect. This can be dried electrolytic capacitors in the primary circuit, and faulty damper elements, as well as dangling resistors or punched semiconductor elements in the stabilization circuits. Possible defective PWM chip from the manufacturer.
If the MYSTERY MTV-1911WL does not have an image, but there is sound and the TV is controlled by the remote control, a malfunction in the backlight circuits of the V185B1-L15 REV.C1 panel is likely. The LEDs or the power converter - LED driver may be faulty. Often in such cases, when you turn on the TV, an image appears and immediately disappears. First of all, it is necessary to verify the operability of the electrolytic capacitors of the rectifier filter supplying the LED driver, and check the LEDs, connecting obviously known good diagnostics.
Often there is a need for disassembling the panel to check the health of the LEDs, as well as contact connections in the connectors and soldering.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required.
Repair of the MSTV2407-ZC01-01 motherboard must begin with the diagnosis and verification of all linear stabilizers and power converters of its microcircuits. Sometimes it may be necessary to update the software (software) - flashing FLASH or EEPROM.
Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing elements of SPI Flash: 25Q32; It requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can be diagnosed by warming up.
If there is no reception of television channels, but the TV works properly from external devices, first of all you need to check the voltage of the tuner F35WT-2A-E and update the software.
Remember! Attempts to self-repair by users of the MYSTERY MTV-1911WL TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!


FIRMWARE FOR SPI FLASH  ----------->   MYSTERY MTV-1911WL, Main: MSTV2407-ZC01-01, Panel: V185B1-L15 REV.C1


 To reduce the backlight current in LED drivers with the AP3039AM controller and the AP3608EM terminal stage (AP3039AM-G1 & AP3608EM-G1), the AP3608EM (AP3608E) microcircuit should proportionally increase the resistor from terminal 14 (ISET) to the housing. The maximum current in each channel (in milliamperes) for the Rset resistor (in kilo-ohms) is determined from the ratio 1.194V / Rset. In channels connected in parallel, the currents add up.
Repair MainBoard
The appearance of the MainBoard MSTV2407-ZC01-01 is shown in the figure below:
MSTV2407-ZC01-01
MSTV2407-ZC01-01 motherboard is combined with a power module. The processor is MST6E182VG, or MST6E181VG, made using BGA technology. Repair of the power module is carried out according to conventional technology, starting with checking its power elements. The following is a functional check of the converters for the processor power: + 1.3V, + 1.8V, 3.3V, based on SY8008B PWM controllers. The power supply of the built-in DDR 2.5V is generated from a 3.3V source using the P-N junction of the 1N4001 diode (3.3V-0.8V = 2.5V). Standby mode is organized from the linear stabilizer series 1117-3V3. The LCD panel is powered by either 5V or 12V, depending on the type of panel used.
MSTV2407-ZC01-01 can be used in TVs:
BBK LEM2249HD Ver2 (Panel LM215DT5D), BBK LEM2284F (Panel M215HG-LE4 Rev.C3), BBK LEM2681F (Panel V260H1-LE10 Rev. C1 ), BBK LEM2682 LEM2682DT (Panel V260B2-LE11 Rev.C1), BBK LEM3284F (Panel HV320WXC-200), Haier LE32T1000 (Panel T320XVN09.0), MYSTERY MTV-2224LW (Panel M215HG-LE4 Rev.C3), MYSTERY MTV-3222LW (Panel T320XVN01.0), MYSTERY MTV-1924LW (Panel V185B1-L17), MYSTERY MTV-3018LW (Panel V290BJ1-PE1), MYSTERY MTV-1911LW (Panel HT185WX7-100), MYSTERY MTV-1922LW (Panel V185B1-L17), MYSTERY MTV-1913LW (Panel HT185WX7-100), MYSTERY MTV-3218LW (Panel HV320WX2-20A), MYSTERY MTV-1918LW (Panel V185B1-L17), MYSTERY MTV-2213LW (Panel M215HGE-L10), MYSTERY MTV-2222LW (Panel M215HG-LE4 REV.C3), MYSTERY MTV-2418LW (Panel HM236WUA-100), MYSTERY MTV-2424LW (Panel HM236WU8-100), MYSTERY MTV-1914LW (Panel V185B1-L15 Rev.c1), MYSTERY MTV-3223LW (Panel LK315T3HB94), MYSTERY MTV-2422LW (Panel HM236WU8–100), MYSTERY MTV-3224LW (Panel T320XVN09.0), MYSTERY MTV-2218LW (Panel CLAA215FA10), MYSTERY MTV-1911WL (Panel V185B1-L15 REV.C1), MYSTERY MTV-3221LW (Panel HV320WX2-268), MYSTERY MTV-2211W (Panel M215HG-LE4 ).
Main features of the MYSTERY MTV-1911WL device:
Installed matrix (LED-panel) V185B1-L15 REV.C1.
To power the backlight LEDs, a converter is used, combined with the main board MSTV2407-ZC01-01, controlled by the AP3039AM, AP3608EM-G1 PWM controller.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 OB2273 microcircuits.
MainBoard - the main board (motherboard) is an MSTV2407-ZC01-01 module, using Cpu microcircuits: MST6E181VS-LF-Z1, Spi Flash: MX25L3206E, Eeprom: 24C16 and others.
The F35WT-2A-E tuner provides television reception and channel tuning.