Sunday 19 April 2020

REPAIR / SERVICING TV DEXP F49D7000C

Technical description and composition of the DEXP F49D7000C TV, panel type and applicable modules. The composition of the modules.
DEXP LED
Model: F49D7000C
Chassis / Version: HLS80JS
Panel: C490F16-E63-H (G71)
LED backlight: 49E6000 LB-C490F16-E60-H-G71-XRD1
T-CON: TT485B01-2-C-4
LED driver (backlight): integrated into PSU
Power Supply (PSU): JUC7.820.00207211
MainBoard: JUC7.820.00205337 HLS80JS
IC MainBoard: CPU: MSD3663LSA-005N, SPI FLASH: GD25Q64
Technical Specifications F49D7000C
DEXP F49D7000C
General repair guidelines for TV LCD LED
Possible malfunctions
- DEXP F49D7000C does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
With such manifestations, a malfunction is most likely to be detected in the JUC7.820.00207211 power module. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches and rectifier diodes in the converters for a short circuit.
In case of breakdowns of semiconductors in secondary circuits, the converter can usually operate abnormally in short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new, or obviously working.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the health in the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED individually with a simple Chinese multimeter (powered by 9 volts) in the P-N-junction test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. A zener diode PN junction indirectly indicates a LED-a
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the JUC7.820.00205337 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). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the CPU elements: MSD3663LSA-005N, SPI FLASH: GD25Q64. BGA chip malfunctions are usually easy to detect by warming up.
Attention TV owners! Attempts to self-repair DEXP F49D7000C are not recommended by the manufacturer and can lead to serious negative consequences!


FIRMWARE FOR SPI FLASH  ----------->   DEXP F49D7000C, Main: JUC7.820.00205337 HLS80JS, Panel: C490F16-E63-H (G71)


 The appearance of the MainBoard JUC7.820.00205337 is shown in the figure below:
JUC7.820.00205337
The appearance of the power supply
Main features of the DEXP F49D7000C device:
Installed matrix (LED-panel) C490F16-E63-H (G71).
The matrix control uses the Timing Controller (T-CON) TT485B01-2-C-4.
To power the backlight LEDs, a converter is used, combined with a power supply.
The formation of the necessary supply voltages for all nodes of the DEXP F49D7000C TV is carried out by the power supply module JUC7.820.00207211, or its analogues.
MainBoard - the main board (motherboard) is a JUC7.820.00205337 module, using CPU chips: MSD3663LSA-005N, SPI FLASH: GD25Q64 and others.
Brand: DEXP, Model: F49D7000C.
Shortly from the TV: LCD, 1080p Full HD, diagonal 49 "(124 cm), HDMI connectors: 3, there is USB, there is support for DVB-T2, backlight type: Direct LED.
Manufacturer: QUANT Plant Zelenograd (Moscow), Driveway 4801, Building 7 and TPV ICS Factory Village. Shushary (St. Petersburg), Moscow highway, 177.
Developer: DNS company. Russia.
The composition uses MainBoard JUC7.820.00205337 HLS80JS and LCD-panel C490F16-E63-H (G71).
Power Supply Unit (PSU) JUC7.820.00207211 Power Supply.
DEXP F49D7000C TV with C490F16-E63-H LCD, 49 "(124 cm) diagonal size of 16: 9 format. The required brightness of the screen is 250 cd / m² LED backlighting. Contrast - the ratio of maximum brightness to minimum is 4000: 1. The LCD panel uses direct pixel illumination with rear LEDs - Direct LED.The TV features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphical decomposition standard 1080p (Full HD). Supported file formats mule timedia: MP3, MPEG4, HEVC (H.265), MKV, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by 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, VGA, HDMI x3, USB. An output for connecting headphones is provided. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
The power consumed by the TV working in the network mode is 95 watts.
Overall dimensions: with stand 1105x694x196 mm, without stand 1105x646x87 mm.
TV Weight: with stand: 9.6 kg, without stand: 9.4 kg.
Attention! The C490F16-E63-H (G71) panel of a DEXP F49D7000C 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.