Monday 27 April 2020

REPAIR / SERVICING TV HYUNDAI H-LED26V5

Technical description and composition of the HYUNDAI H-LED26V5 TV, type of panel and applicable modules. The composition of the modules.
HYUNDAI LED
Model: H-LED26V5
Chassis / Version: 471-01A2-6X701G
Panel: LC260EXN (SD) (A3)
T-CON: LC260EXN-SDA1 6870S-1160A
LED driver (backlight): integrated into T-CON
PWM LED driver: BD9261EFV
Power Supply (PSU): PC3202 40-PC3202-PWC1SG
PWM Power: PWM SOT23-6, L6562D (PFC)
MainBoard: 471-01A2-6X701G
IC MainBoard: EEPROM: 24C64, SPI FLASH: 25Q16
Tuner: F21WT-3BKR-E
Technical Specifications H-LED26V5
HYUNDAI H-LED26V5
General repair guidelines for TV LCD LED
Possible manifestations of defects
- HYUNDAI H-LED26V5 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.
In some of these cases, a malfunction is detected in the PC3202 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 the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM microcircuits are usually checked by replacement with new ones, or obviously working.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
Often in such cases, there is no LED backlight. The reason can be both in the power of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
To check the LED lines for breaks without disassembling the panel, for example, a current source will help. It is impossible to open series-connected PN junctions with a simple multimeter, a voltage of the order of several tens of volts is required.
- 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 471-01A2-6X701G motherboard should begin by checking the stabilizers and power converters needed to power the microcircuit 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 - EEPROM: 24C64, SPI FLASH: 25Q16 and replace failed chips 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 F21WT-3BKR-E tuner, if it is not possible to tune to television channels, make sure that there are supply voltages that must be measured on 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 to users! Self-repair of the HYUNDAI H-LED26V5 TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!

Repair MainBoard
The appearance of the MainBoard 471-01A2-6X701G is shown in the figure below:
471-01A2-6X701G
The appearance of the power supply
Main features of the HYUNDAI H-LED26V5 device:
Installed matrix (LED-panel) LC260EXN (SD) (A3).
The matrix control uses the Timing Controller (T-CON) LC260EXN-SDA1.
An integrated LED driver is used to power the backlight LEDs, it is controlled by the BD9261EFV PWM controller.
The necessary supply voltages for all nodes of the HYUNDAI H-LED26V5 TV are generated by the PC3202 power module or its analogs using PWM SOT23-6, L6562D (PFC) microcircuits.
MainBoard - the main board (motherboard) is a 471-01A2-6X701G module, using EEPROM: 24C64, SPI FLASH: 25Q16 and others.
The F21WT-3BKR-E tuner provides TV reception and channel tuning.

Additional technical information about the panel:
Brand: LG Display
Model: LC260EXN-SDA3
Type: a-Si TFT-LCD, Panel
Diagonal size: 26.0 inch
Resolution: 1366x768, WXGA
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 575.769x323.712 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 350 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V.
HYUNDAI H-LED26V5 TV with a 26 "(66 cm) diagonal LCD display in 16: 9 format. The required screen brightness of 400 cd / m² is provided by LED backlighting. Contrast, as the ratio of maximum brightness to minimum, is 1000: 1 The LED-panel of this TV is equipped with edge LED backlighting - Edge LED. 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 PAL systems, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, JPEG.
The power of the sound system 20 W (2x10 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 x2, audio x4, S-Video, component, 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.
The power consumed by the TV in the operating mode from the network is 110 watts.
Overall dimensions: without stand 654x432x46 mm.
The mass of the TV: without stand: 6 kg.
Attention! The panel of the HYUNDAI H-LED26V5 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.