Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting TVs and Video Sources
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 06-30-2020, 03:30 PM   #1
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default TCL Model 55S405 - No Pic, No Backlight, No Sound - HELP!!!

Hi guys.. I got a tcl tv model 55S425 with no picture, no backlight and no sound. Do you think its an led or main board issue? What do you suggest I buy to fix it?
koolx is offline   Reply With Quote
Old 06-30-2020, 03:33 PM   #2
nomoresonys
Badcaps Veteran
 
Join Date: Jan 2013
City & State: midwest
My Country: U.S.
I'm a: Knowledge Seeker
Posts: 5,632
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

So no indicator light on the front of the tv at all?
nomoresonys is offline   Reply With Quote
Old 06-30-2020, 04:18 PM   #3
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by nomoresonys View Post
So no indicator light on the front of the tv at all?
The screen is dark but you can still make out the menu if you look hard enough. It's a backlight issue to my knowledge.
koolx is offline   Reply With Quote
Old 06-30-2020, 05:00 PM   #4
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Please attach good clear pictures of the whole backside of the TV using 'Go Advanced' so we can see all the boards.
What Voltage testing have you done so far?
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is offline   Reply With Quote
Old 06-30-2020, 10:22 PM   #5
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
Please attach good clear pictures of the whole backside of the TV using 'Go Advanced' so we can see all the boards.
What Voltage testing have you done so far?
Hi budman. I havent done any voltage testing since I'm not versed in that field of electronics. What do you suggest?
koolx is offline   Reply With Quote
Old 06-30-2020, 10:51 PM   #6
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

1) Well, right now we have no idea what we are dealing with since we do not have the TV in front of us to look at.
2) You need to have digital mutli meter and know how to use it to perform some Voltage testing, if you do not have any tools then all you can do is visual inspection or just start buying boards to see if it will fix the problem or not but if you have bad backlights problem then buying boards will be useless, that is why Voltage testing is needed to help narrowing down the problems.
budm is offline   Reply With Quote
Old 07-01-2020, 11:32 AM   #7
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
1) Well, right now we have no idea what we are dealing with since we do not have the TV in front of us to look at.
2) You need to have digital mutli meter and know how to use it to perform some Voltage testing, if you do not have any tools then all you can do is visual inspection or just start buying boards to see if it will fix the problem or not but if you have bad backlights problem then buying boards will be useless, that is why Voltage testing is needed to help narrowing down the problems.
Hi budm. I have a friend who might have a multimeter. If I do get it, will you help me test which components to zero in on on my tv?
koolx is offline   Reply With Quote
Old 07-01-2020, 03:15 PM   #8
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Make sure to read the meter manual first, and the TV needs to be plugged into GFCI outlet for safety then we can go from there.
budm is offline   Reply With Quote
Old 07-01-2020, 04:00 PM   #9
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
Make sure to read the meter manual first, and the TV needs to be plugged into GFCI outlet for safety then we can go from there.
Hi bud.. I did reset the tv through my roku remote while the it was dark. After that I'm able to see "TCL Roku TV" flash once for a split sec but thats it. I can repeat this many times but the tv still wont turn on. Given this do you still think its an led strip issue or something else?

Btw I'm trying to get that multimeter.

Also if its an led strip issue and I buy led strips, do I have to solder them onto the tv?

Last edited by koolx; 07-01-2020 at 04:02 PM..
koolx is offline   Reply With Quote
Old 07-01-2020, 04:09 PM   #10
nomoresonys
Badcaps Veteran
 
Join Date: Jan 2013
City & State: midwest
My Country: U.S.
I'm a: Knowledge Seeker
Posts: 5,632
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Can pick up a basic multimeter for about 10 bucks at the big box stores.
nomoresonys is offline   Reply With Quote
Old 07-01-2020, 04:39 PM   #11
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by koolx View Post
Hi bud.. I did reset the tv through my roku remote while the it was dark. After that I'm able to see "TCL Roku TV" flash once for a split sec but thats it. I can repeat this many times but the tv still wont turn on. Given this do you still think its an led strip issue or something else?

Btw I'm trying to get that multimeter.

Also if its an led strip issue and I buy led strips, do I have to solder them onto the tv?
1) We cannot tell anything until we do some measurement first.
2) If it is bad LED strips, then you will need to dissemble the LCD panel to get to the LED strips. Are good at mechanical assembly/disassembly? This is large panel so a very good chance of breaking it if you have no experience.
budm is offline   Reply With Quote
Old 07-03-2020, 03:09 PM   #12
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
Make sure to read the meter manual first, and the TV needs to be plugged into GFCI outlet for safety then we can go from there.
Hy bud.. ok so my super gave me his sperry mulitmeter. He also gave me a "pen" to check for other measurements. I assume the pen will be used to check the led strips. Let me know if both these devices will suffice and how to start fixing my tv.. thanks bud.
Attached Images
File Type: jpg IMG_20200703_165727.jpg (172.2 KB, 5 views)
File Type: png 1.png (311.5 KB, 5 views)

Last edited by koolx; 07-03-2020 at 03:12 PM..
koolx is offline   Reply With Quote
Old 07-03-2020, 03:12 PM   #13
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

That pen is for probing for active AC for electrician, not going to be use for trouble shooting the TV.
I hope you get the user manual for that meter, it looks like it is made for Electrician.
Please read the manual.
https://www.sperryinstruments.com/en...s-DM2A-Digital
Attached Files
File Type: pdf DM-2A_USE.pdf (582.4 KB, 4 views)

Last edited by budm; 07-03-2020 at 03:22 PM..
budm is offline   Reply With Quote
Old 07-03-2020, 03:22 PM   #14
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
Please attach good clear pictures of the whole backside of the TV using 'Go Advanced' so we can see all the boards.
What Voltage testing have you done so far?
So where are the pictures?
You do have GFCI outlet to plug the TV into, correct?
budm is offline   Reply With Quote
Old 07-03-2020, 05:29 PM   #15
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
Make sure to read the meter manual first, and the TV needs to be plugged into GFCI outlet for safety then we can go from there.
Quote:
Originally Posted by budm View Post
So where are the pictures?
You do have GFCI outlet to plug the TV into, correct?
Hey bud.. I read the manual that youve attached. Although I'm no techie I get the gist of it.

As for a GFCI outlet, I can possibly get one from my super. I'll ask though I doubt he has one.

Below are the pics as you've requested...

***CORRECTION*** My tv is TCL model 55S405. Sorry for the typo in my original post.. I'll change it!

.
Attached Images
File Type: jpg IMG_20200703_191824.jpg (2.61 MB, 8 views)
File Type: jpg IMG_20200703_191831.jpg (2.04 MB, 7 views)
File Type: jpg IMG_20200703_191848.jpg (2.13 MB, 5 views)
File Type: jpg IMG_20200703_191905.jpg (681.0 KB, 4 views)
File Type: jpg IMG_20200703_191939.jpg (545.1 KB, 3 views)

Last edited by koolx; 07-03-2020 at 05:38 PM..
koolx is offline   Reply With Quote
Old 07-03-2020, 05:38 PM   #16
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

1) You should try setting meter to read DC V and measuring some battery Voltage such as AA, car battery to see what it shows on the meter just to get to know your meter because correct DATA of your measurement is very important for us.
2) Your bath room outlet should be protected by the GFCI so you can use the outlet with extension cord. https://www.dfliq.net/blog/what-is-gfci-outlet/
budm is offline   Reply With Quote
Old 07-03-2020, 06:01 PM   #17
koolx
Member
 
Join Date: Jun 2020
City & State: ny, ny
My Country: USA
I'm a: Knowledge Seeker
Posts: 27
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by budm View Post
1) You should try setting meter to read DC V and measuring some battery Voltage such as AA, car battery to see what it shows on the meter just to get to know your meter because correct DATA of your measurement is very important for us.
2) Your bath room outlet should be protected by the GFCI so you can use the outlet with extension cord. https://www.dfliq.net/blog/what-is-gfci-outlet/
Sure I'll have the super help me with that. But fyi I'm not sure you read the last part of my last reply. I edited it after posting it. Just wanted you to know that I made a typo in the title of my thread. The correct model of my unit is 55S405, NOT 55S425. I sent a note of this to the mod and hopefully he should correct it.

I'll let you know when I'm ready for your instruction. Thanks bud!

.
koolx is offline   Reply With Quote
Old 07-03-2020, 06:04 PM   #18
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Please verify the TV full model number.
According to shopjimmy, the boards for the 55S425 do not show the power supply used in your TV, your power supply board is P/N 08-L14TWA2-PW220AL
There are many versions of the same TV model.
https://www.shopjimmy.com/tcl-08-l14...wer-supply.htm
According to SJ, your power supply board is used in 49S405TDAA and 55S405LGAA.
budm is offline   Reply With Quote
Old 07-03-2020, 06:07 PM   #19
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

Quote:
Originally Posted by koolx View Post
Sure I'll have the super help me with that. But fyi I'm not sure you read the last part of my last reply. I edited it after posting it. Just wanted you to know that I made a typo in the title of my thread. The correct model of my unit is 55S405, NOT 55S425. I sent a note of this to the mod and hopefully he should correct it.

I'll let you know when I'm ready for your instruction. Thanks bud!

.
OK, these are the boards used in your TV model 55S405.
https://www.shopjimmy.com/catalogsea.../?q=55S405LGAA

Last edited by budm; 07-03-2020 at 06:11 PM..
budm is offline   Reply With Quote
Old 07-03-2020, 06:43 PM   #20
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 37,867
Default Re: TCL Model 55S425 - No Pic, No Backlight, No Sound - HELP!!!

OK, as you can see, Red connector P2 of the power supply board has pin names located on the bottom side of the board. The exposed pin on the top side of the board are ODD number pins that you can carefully check the Voltage of each pin easily, the EVEN number pins, you will need to use skinny probe to probe the pins from the wire entrance side side of the connect, all the Voltage testing has to be done with all connectors in place.

Turn the TV on and then check the Voltage on each pin, Black probe of the meter connected to the metal chassis of the TV for meter ground reference:
Report the reading as shown in the format below. Make sure to count the pin correctly.
PIN 1: PDIM (PWM Dimming control) = xxx V
PIN 2: BL-ON = xxx V
PIN 3: GND = xxx V
PIN 4: P-ON (PS-ON:mpower supply turn on control signal) = xxx V
PIN 5: N.C. (NO CONNECTION)
PIN 6: A_DIM (Analog Diming control) = xxx V
PIN 7: GND = xxx V
PIN 8: GND = xxx V
PIN 9: 12VDC = xxx V
PIN 10: 12VDC = xxx V
PIN 11: 12VDC = xxx V
PIN 12: 12VDC = xxx V
PIN 13: 12VDC = xxx V
PIN 14: 3D_EN (3D MODE Enable) = xxx V

Pictures provided by shopjimmy.
Attached Images
File Type: jpg Connecttor P2 pin names.jpg (402.6 KB, 7 views)
File Type: jpg Connecttor P2 pins.jpg (313.5 KB, 6 views)
File Type: jpg shopjimmy-08-l14twa2-pw220al-top.jpg (863.4 KB, 6 views)
File Type: jpg shopjimmy-08-l14twa2-pw220al-bottom.jpg (1.09 MB, 6 views)
Attached Files
File Type: txt Connector P2 pin names.txt (381 Bytes, 4 views)
budm is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2020
Powered by vBulletin ®
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 12:50 AM.
Did you find this forum helpful?