searchbox

翻译 使用下拉框 (Language)

Sunday, 28 October 2018

Xiaomi TV (MiTV) has a Black Screen

27 Oct 2018
# MiTV black screen,  faulty LED panel    
https://tinyurl.com/y5kw24kz  google: https://tinyurl.com/y6tcjx6t

This is a common complaint in MiTV and also in other makes.  Some of these black screen faults are caused by OS updates;  others are due to hardware component failures.  The Power Supply Board is usually the culprit.  This article intends to serve as a guide to troubleshoot this black screen problem, using MiTV4 as example.

How MiTV works?

MiTV has only a 3 components;  the Main Board (MB),  the Power Supply Board (PSB)and the Logic Display Board (LDB) or commonly known as T-Con board.  The LDB  Board is usually shielded inside a metal cover.   Behind the plastic and metal covers,  there are also other components such as Bluetooth receiver,  the speaker modules and most important of all,  the LED backlights.   The following shows the layout and back panel of MiTV4;  other models of MiTV are quite similar


The MB  of MiTV4 contains the CPU,  I/O devices and the interfacing components to work with the LDB to light up the LED  panel.  The PSB will supply  12V  power lines to the MB which will do all the necessary startup and "instruct" the LDB, the indicators and the remote controls to work with the LED panel. The PSB also supplies the 96 Volt supply to power the LED backlights.

What can go wrong?

When there is black screen,  it will involve faults in the PSB,  MB and the also the LDB.  If these component boards are healthy,  then the fault could lie in the LED panel,  meaning the interfacing board within the LED panel might be faulty.  When this happen,  the repair will be complex.  Our 55" MiTV4 had a  LED panel fault and was replaced during the 1 year warranty period.

How to detect what went wrong?

The traditional wisdom is to shine a bright torch light as close as possible at the screen and at an angle  to determine if there are moving images on the screen.   In here,  the torch light is simulating the backlight to check if the faulty backlight is the cause.

The following suggestions should help to troubleshoot the faults.

Description  Possible causes and actions Remark
(Dbclick to enlarge video/pictures)

I)  No Moving Image and No Sound

1.  Power Indicating lights not on 1)  Make sure the power is plugged in and the remote control’s battery is good by replacing the battery
2)  If still not working,  press the white start button underneath and at the centre of the TV
Reference video found in YouTube for information
(Click here for full screen)

2.  Indicating lights are on Try to factory reset the OS by pressing the [Confirm] and the [Restore] at the same time and start the TV by pressing the white start button after powering off  the  TV for about 20 seconds (Click here for more information on how to do a factory reset). 
3)  The screen is still in complete darkness If the TV has been synchronized before for screen mirroring,  use the hand phone to check if it can locate  the address to the TV If cannot locate the address of the TV,   most likely the TV is dead with faulty MB or PSB
4)  The screen is back
This screen will be shown on successful factory reset.
https://3.bp.blogspot.com/-BU9C3tYuTwE/WnV4-WnAzLI/AAAAAAAACww/_z9PaukFWc0XY4xxcOc3Sc571deGnbw8ACPcBGAYYCw/s1600/2018-02-03_16h54_52.jpg

II)  Got Moving images and got sound


Suspect PSB has problem supplying power for the backlights
Most likely the LED backlights are faulty.  

Reference video found in YouTube for information
(Click here for full screen)

III)  No moving images but got sound


Check the supply voltages to the LDB and PSB.   Most likely
a)  The LDB is faulty or the LCD screen is faulty
b)  The PSB is faulty

Flow Chart for the Repair

(Double click flow chart for full screen)

https://1.bp.blogspot.com/-udM-2KFhs1E/W9SK-6OCDFI/AAAAAAAADb4/k1xcSCLioPEweOhsU5A4_hqFBmbIitxsACLcBGAs/s1600/2018-10-27_23h57_08.jpg

Why the Power Supply Board  (PSB) can be Faulty?

The Power Supply Board  supplies not only power to the MB but also the power to the LED backlight directly.  When instructed by the MB,  a high voltage (96 volts for 55" MiTV4) will be sent to the  LED backlight to light up the screen.  If there is a faulty LED,  this 96 Volt power rail will be short circuited  and this may damage the PSB.  The LED strip's  PCB rail could be  burnt off,  resulting power  not being supplied to a strip of  LEDs as shown in the following picture.


How To Repair the LED Backlights?

There is no repair video yet for repairing the backlight of MiTV4 series.  In particular,  the MiTV4 has a 9 mm thick LED panel,  requiring Edge LED or ELED type of  backlights  to be installed at the bottom of the LED screen instead of installing it directly behind and underneath the LED panel (Direct LED or DLED)..  Because of this,  many users of MiTV have complained about the heat generated by the backlights at the bottom of TV.   


However,  here is good video about how to replace and test the LED backlights for common and traditional type of  TVs with DLED.  This could apply to other MiTV4 series such as MiTV4A etc


Usually,  users were able to repair most TV problems by first replacing the power supply board,  then follow by the Main board or logic display board in that sequence.  

How to Prolong the life of LED backlights?

Users have been advised to lower the brightness of the TV to about 50%  to 75% so as to reduce the heat caused by the LEDs backlights.   Having proper ventilation at the location where LED backlight is located will prolong its life. 

Where can we buy the MiTV Spares?

MiTV spares are often offered for sale in TaoBao as the vendors stripped old broken TV set to salvage the parts.  They would usually test the boards and give 90 days warranty or money back if the board can be returned within 7 days.   However,  it is always good to ensure that one would not be cheated when buying stuff from TaoBao. 
If one cannot find the spares in TaoBao,  it may be because the MiTV is quite new and one might have to wait for a while.

The Boards of 55" MiTV4

The following pictures are taken from a 55" MiTV4 .  When ordering the part,  give the vendors the correct  parts number copied directly from your TV.  

The Main Board
https://4.bp.blogspot.com/-hK8_vfZbwHM/W9RzfczkswI/AAAAAAAADao/la-IBvFmX2gB8KtMU9znhZdsHKokZPT2QCLcBGAs/s1600/2018-10-27_09h43_15.jpg
The Power Supply Board
https://2.bp.blogspot.com/-wkA2lKolFps/W9R01LbBkLI/AAAAAAAADa0/XAAF6dogJ1ovmpNkTEDSx2DA9Q2cdOXBACLcBGAs/s1600/2018-10-27_09h49_49.jpg

The Logic Display Board
(Different for different panel makers)
https://4.bp.blogspot.com/-WOcbIeJz_Ao/W9R1968h3xI/AAAAAAAADbA/9ap4WGffesQYcDBm5X5G1y4V3ASZniZ_QCLcBGAs/s1600/2018-10-27_09h51_02.jpg

The remote Control Board
https://3.bp.blogspot.com/-qSFlTIT6UWU/W9R2sroIyfI/AAAAAAAADbI/b9XavEt4Gh85iWbLkWi17kzKrEE0gfb6QCLcBGAs/s1600/IMG_1585.JPG

 LED strips w/o alum panel
https://2.bp.blogspot.com/-CszuAemGamU/W9R4dW0BXGI/AAAAAAAADbU/l9aFLKyuqcUzyT74PUc8A1jLOMB8j76DgCLcBGAs/s1600/2018-10-27_22h36_31.jpg

LED strips inside alum panel
https://3.bp.blogspot.com/-0tKpzkoppD4/W9R5YKCg3nI/AAAAAAAADbg/42FeEeIhVls-qgeiHCDor_F3I3Z7DuFxgCLcBGAs/s1600/2018-10-27_22h42_06.jpg

Speakers and Remote control
https://3.bp.blogspot.com/-45y50Cm-7t0/W9R7SmcYLSI/AAAAAAAADbs/KXni1vLcvwk0VsuGV6KPWR4vbKkjvHd2QCLcBGAs/s1600/2018-10-27_22h49_53.jpg








Other Similar Articles

tinyurl :    https://tinyurl.com/y8cyr4w7

66 comments:

  1. Today tv showing only mi in black screen
    What the problem?
    Plz rply

    ReplyDelete
    Replies
    1. This can happen when you have a problem in the OS update, faulty main board, faulty LED panel and a faulty Power supply board. the easiest way is to do a factory reset, if that is not possible then it must be something wrong with the electronics or the LED panel. If it is the latter, the usual recommendation is to change the TV as the replacement of LED panel can be very expensive

      Delete
    2. I was having this issue before two days ago, I had complained for the same to the Mi service center, service person had told me that there is a panel issue.
      I had asked for the charges to resolve this issue and he repliesd that it will charge around 31000 with GST.
      So I hope you can understand the product quality.
      It has just completed it's 2.2 years.

      Delete
    3. I am also facing same issue now MI replied me to change the screen costing around 32000 plus GST plus service charge TV is just 2.2 years old

      Mi has to improve a lot

      Delete
  2. Hi all. Thank you so much for the post. Actually i am facing problem exact the same mentioned that my mitv4 55" black screen but with sound. I am now opened the tv, while i can't find the logic display board as you picture mentioned above, is that hidden inside the metal cover? coz i want to find the model no. and buy the new one from taobao. Can you give me some suggestions, thanks!

    ReplyDelete
    Replies
    1. For MiTV4, the logic display board is built into the LED panel. If the logic dislay board is faulty, the recommendation is to replace the LED panel which will not be cost effective.

      Delete
    2. OIC! It seems not worth to replace the new LED panel. Thank you for the professional suggestions!

      Delete
  3. For my MI TV4(55 inch), If i do the reset, the TV is working for few hours before going to black screen. It works again if I do reset after 10 minutes and same problem continues. What will be the problem?

    ReplyDelete
    Replies
    1. Not quite sure. May be the power supply board is faulty due to some components overheating.. try to open the back cover and blow air to cool the power supply board

      Delete
    2. same things happent for my MI TV4(55 inch)in the same period 28th december 2019, so the causes of faultness might be update.

      Delete
    3. Was your issue fixed?i have similar problem

      Delete
    4. @SkyJuice123
      Hi, my MI tv 4a 65 inch, display goes blank after few seconds of turning it on. MI, Innovation for everyone, then the screen is blank like some wallpaper stuff. I can play music and videos, youtube, sound is on, but no visuals. Please suggest.

      Delete
    5. Any solution for this problem?

      Delete
  4. My Mi TV 4s SE 43" is occuring power indicator is on,but no display what should I do.
    Please Reply Me.

    ReplyDelete
  5. Vertical coloured lines in my mi tv. What to do?

    ReplyDelete
  6. Due to some wrong setting i done in my tv after that screen goes black and only power on light blink after pressing remote switch. Pls help

    ReplyDelete
  7. My mi smart tv screen goes black and nothing show in display because due to to some wrong setting i am done in tv setting .pls give me some solution

    ReplyDelete
  8. Mi tv 4A pro... display not working... we can hear all the sounds but no display... pls tell me the solution

    ReplyDelete
  9. My mitv 4a screen is blacking after updating system soft.

    ReplyDelete
  10. My Mi TV 4A 32 inch is repeatedly asking for input source then appears normal for few minutes and again asks for input source and auto selects itself and so on. It repeatedly asks for input source even though we need to select the source only once upon startup.

    ReplyDelete
  11. Same problem facing in 4a pro 43" tv

    ReplyDelete
  12. led display screen Shenzhen HTJ Technology Co., Ltd. is a professional LED display manufacturer with a history of more than ten years, aiming to provide one-stop full color LED screen solution to clients in global market from sales, transportation, custom clearance, installation, training and maintenance service.

    ReplyDelete
  13. My Mi TV 4a SE49* is occuring powar indcator is on but no display what shoud i do please reply me or caal me 8669047416

    ReplyDelete
  14. Mi led 55' did not show any power indicator light

    ReplyDelete
  15. I have a problem with my new 55" MI TV 4S...A vertical transparent gray band appear on all channels, inputs, and apps!
    This vertical line is more visible when the background image is gray or white than when the background is dark ... for example when using a browser and pages with text!

    ReplyDelete
  16. I have a problem with my new 55" MI TV 4S...A vertical transparent gray band appear on all channels, inputs, and apps!
    This vertical line is more visible when the background image is gray or white than when the background is dark ... for example when using a browser and pages with text!

    ReplyDelete
  17. I have a problem with my new 55" MI TV 4S...A vertical transparent gray band appear on all channels, inputs, and apps!
    This vertical line is more visible when the background image is gray or white than when the background is dark ... for example when using a browser and pages with text!

    ReplyDelete
  18. Mi TV 2 49" showing mi logo and disappear later, leaving white light start button fading in and out, bluetooth remote were spoilt, using mobile app as remote control so far, how may i factory reset without a proper remote?

    ReplyDelete
  19. Worst TV company I have seen. Worst product.

    ReplyDelete
  20. You have got some great posts in your blog. Keep up with the good work. Get digital signage in Singapore

    ReplyDelete
  21. Thanks for posting this info. I just want to let you know that I just check out your site and I find it very interesting and informative. Digital signage singapore

    ReplyDelete
  22. The Amazon Fire Stick is one of the most popular devices liked by most of the people globally because they are cheap and have easy setup and use. They are relatively powerful but sometimes fire stick black screen occurred.

    ReplyDelete
  23. My Mi TV 52 is display blue screen no display with sound Wat's d problem plz reply

    ReplyDelete

  24. Dissertation Writing Help


    Most enticing blogs I’ve ever read and this is what it should. Must be shared as well. I was really bored but your blog lightened up my day


    Buy UV Ballast

    ReplyDelete
  25. Hi there, probably you could help me, my Mi TV 4s flashes red, blue, green, black, white colours when it is on....nothing else is displayed...but the sound seems to work...what could be the issue?

    ReplyDelete
  26. My tv shows half of black and half white May I know the problem

    ReplyDelete
  27. My mi tv4a has gone black, if I look close I can see the tv app icons like Netflix and others and can also use the remote to switch from one app to another, also the sound works fine, please help.

    ReplyDelete
  28. The problem is an issue that too few folks are speaking intelligently about. I'm very happy that I found this during my search for something regarding this.
    Best Monitor Guide

    ReplyDelete
  29. 我的 mi L55M5-AD 开机时只出现藍底螢幕什么畫面也沒有,請問什麼故障?

    ReplyDelete
  30. Hi, my MI tv 4a 65 inch, display goes blank after few seconds of turning it on. MI, Innovation for everyone, then the screen is blank like some wallpaper stuff. I can play music and videos, youtube, sound is on, but no visuals. Please suggest.

    ReplyDelete
  31. My mi TV 4 pro has suddenly appeared a black screen
    Sound only working,and complaining to customer care
    Technician came to my home they not even touch my TV suddenly they told me to change the led display or change the board of the TV it will be around 30k what can i do someone help with this!..

    ReplyDelete
  32. 19" indoor advertising screen,frameless lcd advertising display, electronic advertising board

    China wholesale 19" indoor advertising screen,high quality frameless lcd advertising display, open frame electronic advertising board, digital screen advertising,electronic lcd display

    Visit here:- Indoor lcd display

    ReplyDelete
  33. Commercial Display Manufacturer Co Ltd is the specialist Digital signage supplier, providing heavy-duty 10" LCD advertising display, digital signage display.

    Visit here:- Lcd advertising display

    ReplyDelete
  34. My mi 55 inch tv has blank screen how can it be repaired at min cost

    ReplyDelete
  35. While watching the mi tv the screen gets black for some seconds and thn it just get normal, it happens a lot any solutions?

    ReplyDelete
  36. While watching the mi tv the screen gets black for some seconds and thn it just get normal, it happens a lot any solutions?

    ReplyDelete
  37. Hello. I'm having a problem with my Xaomi MiTv 4s. We were watching tv and then the screen turned black. When we start the tv we see the difference when it's on and off. But either way we only see a black screen. What can we do to solve the problem? We have contacted the company that we brought from and they can't do anything because we bought from a different country. But we are hoping we can fix the television on our home without more contacts from the company. Can you help us?

    ReplyDelete
  38. 42 inch free standing digital signage,large digital display,kiosk media player

    Southern Stars Enterprises Co Ltd is the specialist manufacturer for commercial display since 1996. All our products are heavy-duty built to suit super long hour loop-playing 24/7/365,including our 1080P 42 inch free standing digital signage,floor stand large digital display,fashion kiosk media player,media signage,digital media signage etc..

    Visit here:- Digital signage kiosk

    ReplyDelete
  39. Hi, I have mi tv 4 lm55m5 ab, The tv blink on and off with a vertical black bar in the left side of the screen, what can I do? If I lower the brightness to 2 (low brightness) the tv stop blinking but there still a black vertical bar. What can I do?

    ReplyDelete

  40. I have mi tv 4 lm55m5 ab, The tv blink on and off with a vertical black bar in the left side of the screen, what can I do? If I lower the brightness to 2 (low brightness) the tv stop blinking but there still a black vertical bar. What can I do? What do you think is the problem
    Realy hope that you can help me! Thank you.

    ReplyDelete

  41. I have mi tv 4 lm55m5 ab, The tv blink on and off with a vertical black bar in the left side of the screen, what can I do? If I lower the brightness to 2 (low brightness) the tv stop blinking but there still a black vertical bar. What can I do? What do you think is the problem
    Realy hope that you can help me! Thank you.

    ReplyDelete
  42. Display not working why is the problem

    ReplyDelete
  43. Hi i bought my MI 4X 55 INCH, ONE WEEK AGO ONLY MY TV NOT WORKING.

    SHOWING BLACK SCREEN
    NOT TURNING ON

    PLS HELP ON THIS
    I DIDN'T EXPECT FROM MI

    NO CUSTOMER CARE IS CARING

    PLS HELP ME HOW TO REACH CUSTOMER CARE SERVICE.

    MY WHATSAPP CONTACT.
    +91 9704227741

    ReplyDelete
  44. Commercial Display Manufacturer Co Ltd is the specialist Digital signage supplier, providing heavy-duty 10" LCD advertising display, digital signage display.

    Visit here:- Lcd advertising display

    ReplyDelete
  45. I purchased QLED 55 MI TVon 1st June 2021, on 16th June display has gone and from then continuously approaching MI for service support but till now there is no reply or support. One of pathetic TV and service . I have paid 59k for this faulty TV. Someone please help me

    ReplyDelete
  46. MI TV 32 inch black problem Paisa Kitni hotel

    ReplyDelete
  47. Mi LED 65' TV has a brightness problem. although everything is visible the brightness is very low, even when dynamic backlight is switched on and brightness is maxed out. even the Mi that appears on power on is dimmed down. this is the same even after i did a wipe data and factory reset.

    ReplyDelete
  48. It is really very helpful for us and I have gathered some important information from this blog.
    Xiaomi Redmi Repair Center in Chennai

    ReplyDelete
  49. Cheaper to buy new one? Or repair..mine is 43 inch mi TV n used for two years

    ReplyDelete

Stock Market of China, Taiwan, Hong Kong and the US in One Chart

30 July 2022 This article is making an attempt to find how the various stock markets in China,  Taiwan,  Hong Kong, and the US interacted wi...