Tcl 55S405 bad T-con?

[mikalcarbine]

My TCL just went on the fritz last night, purchased November 2017. From what I've been reading I think this is the T-con board but would like others' opinions or suggestions.

Boards physically look OK, only two caps on the power supply and they look fine, voltages coming off power supply with load look OK. The voltage pins are poorly labeled, I'll need to spend a little extra time taking measurements before ordering anything

Here's a video, let me know if the link doesn't work
https://photos.app.goo.gl/BKQRS9mhvMiCJELw5

[mikalcarbine]

Re: Tcl 55S405 bad T-con?

Future reference for anyone who finds this, replaced the T-con and all is working normal now.

[nomoresonys]

Re: Tcl 55S405 bad T-con?

Thanks Mikalcarbine, good example why you shouldn't jump to conclusion of bad panel because it can be hard to tell, can be just the tcon as in your case.

[DeatRaton]

Re: Tcl 55S405 bad T-con?

I'm assuming I have a bad tcon board as well. I have a line going down the screen, no cracks, and the film at the bottom of the TV seem to be in good shape, I touch all of them and nothing changes. The line remains solid. Can someone confirm tcon might be my problem?

[neilc6]

Re: Tcl 55S405 bad T-con?

Solid lines are usually panel problems and not the tcon.

[celloyd]

Re: Tcl 55S405 bad T-con?

Can you share what your problem was that caused you to replace the tcon board? My TCL would turn on and show the screen and sometimes not. I could unplug and plug back in and it would work but eventually the picture never came back no matter what i did. I could always hear the sounds when I used the remote, just no picture. I was planning to buy a repair kit and replace the whole works but if I don't have to, that would be even better. Any trouble shooting help would be GREATLY APPRECIATED!

[nomoresonys]

Re: Tcl 55S405 bad T-con?

If the backlights are not coming on, shine a flashlight at the screen look closely maybe hit the menu button on tv or remote, see if you can see text or anything on screen.

[celloyd]

Re: Tcl 55S405 bad T-con?

If the backlights are not coming on, shine a flashlight at the screen look closely maybe hit the menu button on tv or remote, see if you can see text or anything on screen.

I'll need to check when I get home but I'm pretty sure the screen lights up, just don't see the "wallpaper" of the start page. Shows me a dark grey screen. I also read where if you let it sit for an hour, you might have luck with a reset. I have not tried that yet, either.

[nomoresonys]

Re: Tcl 55S405 bad T-con?

Also test the fuse on tcon, should be about 12 volts on each side, black negative test probe on chassis/metal panel, red probe on each side.

[celloyd]

Re: Tcl 55S405 bad T-con?

Also test the fuse on tcon, should be about 12 volts on each side, black test probe on chassis/metal panel, red probe on each side.

Thanks!! I will hopefully get to this tonight and report back.

[celloyd]

Re: Tcl 55S405 bad T-con?

Also test the fuse on tcon, should be about 12 volts on each side, black negative test probe on chassis/metal panel, red probe on each side.

Okay, not sure where the fuse is? Also, it needs to be plugged in to test volts, correct?

[nomoresonys]

Re: Tcl 55S405 bad T-con?

Yep plug in hit power see if it's there, fuse should be close to where the cable comes in from the mainboard, on tcon, should be labeled starting with F, like F1 or sum such.

[celloyd]

Re: Tcl 55S405 bad T-con?

Yep plug in hit power see if it's there, fuse should be close to where the cable comes in from the mainboard, on tcon, should be labeled starting with F, like F1 or sum such.

I'd like to post a pic and have someone point it out for me? My old eyes are not seeing it.

[diif]

Re: Tcl 55S405 bad T-con?

F1

[celloyd]

Re: Tcl 55S405 bad T-con?

F1

Thanks!! So I tested it, reads 16v on one side and 0 on the other assuming I am doing it correctly. So tiny that it's hard to know if I'm hitting the right spot. Does this sound reasonable and if so, where do I go from here; what is this telling me?

[budm]

Re: Tcl 55S405 bad T-con?

If one end of the fuse shows 0V that means the fuse has blown.

[celloyd]

Re: Tcl 55S405 bad T-con?

If one end of the fuse shows 0V that means the fuse has blown.

So...replace the TCON board and I'm good to go? Do I need to further investigate the cause of the blown fuse? Hate to replace this board only to have the same issue happen again.

[budm]

Re: Tcl 55S405 bad T-con?

Since you do not have the schematic of the T-CON board, you should start checking the RESISTANCE of the caps on that T-CON board to see if any one of them shows very low resistance (<10 Ohms) or not, if you find shorts the disconnect the cables between T-CON and the LCD panel to see if the shorts will go sway or not.

[Louis82]

Re: Tcl 55S405 bad T-con?

Hi Budm,
Have you guys been able to find what is the cap or component that fails in this T-CON board? I have checked all caps and no short on caps or IC's.
Any suggestion or update on this TCON board repair?
Thanks!