Tuesday 14 April 2020

REPAIR / SERVICING TV ERISSON 32LET70

Technical description and composition of the ERISSON 32LET70 TV, panel type and applicable modules. The composition of the modules.
ERISSON LED
Model: 32LET70
Chassis / Version: MS82S
Panel: 1080p Full HD, 1920x1080
Mainboard: MS82S
IC MainBoard: CPU: mst6e182vs-lf; SPI Flash: 25q32;
Tuner: 07-380FI5-NK4G
Specifications 32LET70
ERISSON 32LET70
General repair guidelines for TV LCD LED
An external examination of the external and internal elements should be carried out in a timely manner before the start of operations for their dismantling. Sometimes, based on visible changes in the components of the device, it is possible to draw some conclusions and determine the direction of further troubleshooting even before the necessary measurements are taken. Carbonized paint on the upper layer of resistors, electrolytic capacitors of rectifier filters swollen after boiling, cracked soldering at the terminals of heating elements or transformers can often suggest the cause of the defect and possible consequences.
If the ERISSON 32LET70 does not turn on, no control lights on the front panel light up or blink, therefore, there is a very high probability of a power module malfunction. In some cases, only the processor power regulator may be faulty. When diagnosing and repairing the power supply, after replacing the swollen capacitors of the secondary rectifier filters (if any), you must first check the mains fuse. When it is broken, the power elements of transistors and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
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.
In cases where the ERISSON 32LET70 TV has lost the image, and the sound is there and all the other functions are operational, there is a possibility of a malfunction of the LED driver (converter for powering the backlight LEDs of the panel 1080p Full HD, 1920x1080). When you turn on the TV, the image may appear briefly and disappear immediately. It must be borne in mind that with such manifestations the LEDs themselves also fail.
Often in the absence of backlighting, disassembling the panel is required. It is necessary to check the serviceability of the transitions of the LEDs, as well as the reliability of the contact connections in the rulers and connectors.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes.
When trying to repair the motherboard, you should first check the serviceability of linear stabilizers or power converters of microcircuits and, if necessary, update the software (software).
In cases of attempts to repair the MB board (SSB), it is necessary to check the health of its elements - CPU: mst6e182vs-lf; SPI Flash: 25q32; which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Before replacing the tuner 07-380FI5-NK4G, if there is no tuning for the channels, you must first check the supply voltage at its terminals.
Owners and users of the ERISSON 32LET70 TV must remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!

FIRMWARE FOR SPI FLASH  ----------->   ERISSON 32LET70 MS82S, Main: MS82S, Panel


 Service Mode: Menu -> Image -> Contrast -> 1950 (9735).

 Main features of the ERISSON 32LET70 device:
Installed matrix (LED-panel) 1080p Full HD, 1920x1080.
The required supply voltage for all nodes of the TV ERISSON 32LET70 provides a switching power supply.
MainBoard - the main board (motherboard) is an MS82S module using CPU chips: mst6e182vs-lf; SPI Flash: 25q32; and others.
The tuner 07-380FI5-NK4G provides reception of television programs and tuning to channels.
 Trademark: ERISSON, Model: 32LET70.
Short from TV: LCD, 1080p Full HD, 32 ”(81 cm) diagonal, HDMI: 2, USB: 2, backlight type: Edge LED.
The composition uses MainBoard MS82S and an LCD panel (matrix) 1080p Full HD, 1920x1080.
ERISSON 32LET70 TV with a 1080p LCD display, 32 "(81 cm) diagonal size in 16: 9 format. The required brightness of the screen is 350 cd / m² due to LED backlighting. Contrast, as the ratio of maximum brightness to minimum, is 1000: 1. The LED panel of this TV has end LED backlighting - Edge LED.The TV's design and technical capabilities include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphic resolution of 1080p (Full HD) standard. The source 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, DivX, JPEG.
The power of the sound system 6 W (2x3 W) provide 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, SCART, RGB, VGA, HDMI x2, USB x2. 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, 1360x768.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C standards.
Overall dimensions: With stand 463x360x45 mm, Without stand 463x310x134 mm.
Attention! The 1080p Full HD, 1920x1080 panel of an ERISSON 32LET70 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.