Monday 13 April 2020

REPAIR / SERVICING TV ERISSON 19LK20

Technical description and composition of the ERISSON 19LK20 TV, panel type and applicable modules. The composition of the modules.
ERISSON
Model: 19LK20
Chassis / Version: MST6M58-T6S
Panel: 720p HD, 1366x768
Inverter (backlight): 467-0101-12501G
Power Supply (PSU): 465-01A2-18001G
PWM Power: LD7575B (PWM flyback)
MainBoard: MST6M58-T6 S
IC MainBoard: MST6M58FQP-LF-Z1, EN25B64-100FIP, FM24C64, A3R12E4JFF, MP1482DS, SA7454
Tuner: CDT-3FP2I2-31
Specifications 19LK20
ERISSON 19LK20
General recommendations for repairing TV LCD
ERISSON TV made on the MST6M58-T6S chassis, like many other electronic devices, it is advisable to start repairing by inspecting all external and internal elements. In some cases, visible external damage to the elements can indicate the direction of troubleshooting and localization of the defect even before the start of the necessary measurements at the control points of electronic circuit nodes. If ring cracks are detected in the soldering of the terminals of the elements or dangling connecting tracks, swollen capacitors or charred resistors - all this can be characteristic signs of the causes or consequences of an already known typical malfunction.
In the absence of any signs of operability, when the ERISSON 19LK20 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 supply module 465-01A2-18001G. With the same manifestations, the power regulator of the control processor on the motherboard may be faulty. In the general case, first of all, it is necessary to check the electrolytic capacitors of the secondary rectifier filters and the fuse at the input of the network. If it is broken, then you should check for breakdown of the PN junctions of the rectifier bridge diodes and the key transistor of the converter, which can either be on a separate radiator or integrated with a PWM controller in a common chip. Possible options.
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 ERISSON 19LK20 does not have an image, there is sound and the channels are switched, there is a possibility of a malfunction of the display backlight, or their power converter - inverter. Sometimes when you turn on the image appears and disappears immediately. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the inverter itself, including in the secondary rectifier of the main PSU. If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
The MST6M58-T6S motherboard is subject to verification if there is no reaction to the remote control and function buttons, the standby indicator blinks or lights up continuously. In such cases, if the converters or power regulators of the microcircuit are working, a software update may be necessary. In some cases, it is necessary to check or replace (if necessary) the elements of the MB board (SSB) - Flash EN26B64. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
Attention! For users and owners of 19LK20 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.


FIRMWARE FOR SPI FLASH  ----------->   ERISSON 19LK20, Main: MST6M58-T6S, Panel: 720p HD, 1366x768



 The appearance of the MainBoard MST6M58-T6 is shown in the figure below:
MST6M58-T6
MST6M58-T6 can be used in TVs:
ERISSON 19LK20 (Panel 720p HD 1366x768), ERISSON 20LK15 (Panel 720p HD 1366x768), ERISSON 23LK20 (Panel LM230WF1 (TL)(F3)).
The appearance of the power supply
Main features of the ERISSON 19LK20 device:
Installed matrix (LCD panel) 720p HD, 1366x768.
An inverter 467-0101-12501G is used to power the backlight.
The necessary supply voltages for all nodes of the TV ERISSON 19LK20 are generated by the 465-01A2-18001G power supply module, or its analogs using LD7575B (PWM flyback) microcircuits.
MainBoard - the main board (motherboard) is an MST6M58-T6 module, using chips MST6M58FQP-LF-Z1, EN25B64-100FIP, FM24C64, A3R12E4JFF, MP1482DS, SA7454 and others.
The tuner CDT-3FP2I2-31 provides the reception of television programs and tuning to channels.

 Trademark: ERISSON, Model: 19LK20.
Briefly from the TV: LCD, 720p HD, diagonal 19 "(48 cm), HDMI: 2, USB.
The composition uses MainBoard MST6M58-T6 S and an LCD panel (matrix) 720p HD, 1366x768.
Power Supply Unit (PSU) 465-01A2-18001G Power Supply.
ERISSON 19LK20 TV with a 720p LCD display, 19 "(48 cm) diagonal size of 16: 9 format. You can view HD images 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 analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, MPEG4, MKV, JPEG. Stereo audio is implemented with two built-in speakers using a processing system Ki audio NICAM STEREO.
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.
Overall dimensions: With stand 769x536x196 mm, Without stand 392x260x40 mm.
Attention! The 720p HD, 1366x768 panel of an ERISSON 19LK20 LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!