Technical description and composition of the BBK LEM4279F TV, panel type and applicable modules. The composition of the modules.BBK LED
Model: LEM4279F
Chassis / Version: V2.0 S24NZ0A0NNRWA E182VG
Panel: SEL420V6-S00E Rev. R1 PCB: C3 LED: S442
LED driver (backlight): JLH94-V0C, ST401-1641 SKD 168P-42DWM
Power Supply (PSU): 5800-P42EWB-W000 VER 00.00
PWM Power: FSFR1700XSL, OB5223AP, OB6572CP (PFC)
MainBoard: E182VG-z0-A0
IC MainBoard: MSH9010-LF, IT6633E-P, 25Q128V51Q, MST182VG, RT8296A, R620D, BM3407, SY8008B, SX8660Z
Tuner: R620D
Control: RC-LEM3279
Technical Specifications LEM4279F
BBK LEM4279F
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The BBK LEM4279F TV does not turn on at all. There is no reaction to the remote control or to the control buttons from the front panel. Indicator lights do not light or flash.
Most often, with such manifestations, the main power module 5800-P42EWB-W000 is found to be faulty. It is necessary to measure its secondary output voltages, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse 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 an excess of the maximum current or voltage. 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). It is checked only by replacement with a known good one.
- 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 can be both in the power supply 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 strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, sometimes you can detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the E182VG-z0-A0 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). Sometimes it is necessary to check or replace (if necessary) the elements of the MainBoard board - MSH9010-LF, IT6633E-P, 25Q128V51Q, MST182VG, RT8296A, R620D, BM3407, SY8008B, SX8660Z. In cases where the BGA processor is used, its malfunction is usually detected by local heating.
Before replacing the R620D tuner, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via I2C
Attention to users! Independent repair of the BBK LEM4279F TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> BBK LEM3279, LEM3289, LEM3279F, LEM3289F, LEM4079F, LEM4289F, LEM4289F
The appearance of the MainBoard E182VG-Z0-A0 is shown in the figure below:E182VG-Z0-A0
E182VG-Z0-A0 can be used in TVs:
BBK LEM3279F (Panel T320HVN01.2 / SEL320V8-S0JB), BBK LEM4079F (Panel SEL390V7-S00E (WXGA)), BBK LEM4279F (Panel SEL420V6-S00E Rev.R1 PCB:C3 LED:S442), BBK LEM4289F (Panel SEL420V6-S00E).
Main features of the BBK LEM4279F device:
Installed matrix (LED panel) SEL420V6-S00E Rev. R1 PCB: C3 LED: S442.
The LED driver JLH94-V0C is used to power the backlight LEDs.
The necessary supply voltages for all nodes of the TV BBK LEM4279F are generated by the power supply module 5800-P42EWB-W000, or its analogs using chips FSFR1700XSL, OB5223AP, OB6572CP (PFC).
MainBoard - the main board (motherboard) is an E182VG-z0-A0 module, using microchips MSH9010-LF, IT6633E-P, 25Q128V51Q, MST182VG, RT8296A, R620D, BM3407, SY8008B, SX8660Z and others.
The R620D tuner provides TV reception and channel tuning.
Brand: BBK, Model: LEM4279F.
Briefly from the TV: LCD, 1080p Full HD, diagonal 42 "(107 cm), HDMI: 3, USB, backlight type: Edge LED.
The composition includes MainBoard E182VG-z0-A0 and an LCD panel (matrix) SEL420V6-S00E Rev.R1 PCB: C3 LED: S442.
Power Supply Unit (PSU) 5800-P42EWB-W000 Power Supply.
BBK LEM4279F LED TV with SEL420V6-S00E LCD display, 42 "(107 cm) diagonal size in 16: 9 format. The required screen brightness of 450 cd / m² is provided by LED backlighting. The ratio of maximum brightness to minimum (contrast) is 4000 : 1. This model uses Edge LED backlighting, and the design and technical features of the TV include watching broadcasts and movies in high quality HD with a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD). Input high-frequency or video signal It 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, JPEG. Stereo sound is realized by two built-in speakers .Uses NICAM STEREO audio processing system.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, SCART, VGA, HDMI x3, 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, 1360x768.
The power consumed by the TV in the operating mode from the network is 80 watts.
Overall dimensions: 1000x668x222 mm.
The mass of the TV: 17 kg.
Attention! The SEL420V6-S00E Rev.R1 PCB: C3 LED: S442 panel of the BBK LEM4279F 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.