Sunday 22 March 2020

REPAIR / SERVICING TV BBK 24LEM-1001

Technical description and composition of the BBK 24LEM-1001 TV, type of panel and applicable modules. The composition of the modules.
BBK LED
Model: 24LEM-1001 / T2C
Chassis / Version: V1.0 920A3NN
Panel: M236X12-E3-C (G2) // V236BJ1-LE1 HD
LED driver (backlight): JUG7.820.846 // JUG7.820.1005-1 (EUP2589)
PWM LED driver: HAI7101PB
Power Supply (PSU): PW52057C Rev01
PWM Power: LD7750RGR
MainBoard: JUG7.820.1426 // JUG7.820.10
IC MainBoard: TSUMV59XES-XG, YD1517
Control: RC-LEM101
Technical Specifications 24LEM-1001
BBK 24LEM-1001
General repair guidelines for TV LCD LED
Possible malfunctions
- The BBK 24LEM-1001 TV does not turn on and does not show any signs of operability at all. There is no reaction to either the remote control or the front panel control buttons.
Failure in such cases should be sought in the PW52057C power supply circuits. It is necessary to measure the 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 elements of the primary circuit, the mains fuse usually breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, power supply, frequency-setting, damper ... as well as elements of the Negative Stabilization Feedback. PWM chip LD7750RGR can also cause a malfunction of the power switch of the converter and is checked by replacement.
- 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.
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
When trying to detect a break in the LED lines, it should be taken into account that it is difficult to do this without disassembling the panel. For example, a current source is needed to open PN junctions connected in series.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the JUG7.820.1426 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). Sometimes it is necessary to check or replace (if necessary) the elements of the MainBoard board - TSUMV59XES-XG, YD1517. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
Attention! For users and owners of 24LEM-1001 TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.

Alternative option:
BBK 24LEM-1001 / T2C - chassis (Main Board): JUG7.820.10, Spi Flash: 25Q64, Panel: V236BJ1-LE1 HD, Power: PW52057C, Led Driver: JUG7.820.1005-1, LED power = 30V.




The appearance of the MainBoard JUG7.820.1426 is shown in the figure below:
JUG7.820.1426
The appearance of the power supply
Main features of the BBK 24LEM-1001 device:
Installed matrix (LED-panel) M236X12-E3-C (G2) or V236BJ1-LE1 HD.
The LED driver JUG7.820.846 is used to power the backlight LEDs, it is controlled by the HAI7101PB PWM controller.
The necessary supply voltages for all nodes of the TV BBK 24LEM-1001 are generated by the PW52057C power module, or its analogs using LD7750RGR microcircuits.
MainBoard - the main board (motherboard) is a JUG7.820.1426 module, using TSUMV59XES-XG, YD1517 and others.
 Brand: BBK, Model: 24LEM-1001.
Shortly from the TV: LCD, 720p HD, diagonal 24 "(61 cm), has HDMI, has USB, backlight type: Edge LED.
The composition uses MainBoard JUG7.820.1426 and an LCD panel (matrix) M236X12-E3-C (G2), or V236BJ1-LE1 HD.
Power Supply Unit (PSU) PW52057C Rev01 Power Supply.
BBK 24LEM-1001 LED TV with M236X12-E3-C (G2) LCD, 24 "(61 cm) diagonal size of 16: 9 format. The required brightness of the screen is 220 cd / m² with LED backlight. Maximum brightness ratio to the minimum (contrast) is 3000: 1. This model uses side illumination from Edge LEDs. You can view images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic Digital signal processing and generation takes place in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, DivX, MKV, JPEG. Stereo sound is realized by two built-in speakers. An audio processing system is used. NICAM STEREO.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, VGA, HDMI, 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, 1280x1024.
Overall dimensions: With a support of 576x388x180 mm, Without a support of 576x350x56 mm.
TV Weight: 3.7 kg.
Attention! The M236X12-E3-C (G2) panel of the BBK 24LEM-1001 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.