TCL 55US57 Bad Tcon Or Bad Panel Boards

[Michale32086]

Got a nice TCL in.. 55US57..

I have dealt with a few of these, but there issues were backlights..

This one, the backlights are fine, I just get no display at power up..

I have found that, if I take off the right connector that goes from the TCON to the Panel Boards, I get display on the Left side of the TV...

That tells me either it's a bad TCON (hope hope) or a bad left side panel board...

If it's the panel board, it's likely unfixable..

Is there a way to determine conclusively whether it's the TCON or Panel Board???

Other than replacing the TCON...

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

What did you get when you did the other ribbon cable?

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

What did you get when you did the other ribbon cable?

Backlights.. no display on panel.. Sorry.. Meant to add that detail..

[budm]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

https://www.badcaps.net/forum/attach...1&d=1574193881
Start checking the RESISTANCE of those MLCC on that tab bonding board of the bad side.

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

https://www.badcaps.net/forum/attach...1&d=1574193881
Start checking the RESISTANCE of those MLCC on that tab bonding board of the bad side.

Awesome.. Thanx...

Uh.. Forgive my ignorance. Can you circle an MLCC??

[budm]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Those brown tan caps.

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Those brown tan caps.

Checked the first three.. Marked..

1600 Mohms +/- 10-20ish

[budm]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

You need to check all of them.
BTW, you meter can read 1600 Mega Ohms?

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

You need to check all of them.

Will do... As soon as I get back to the shop.. Is that a normal correct reading for those?? 1600 +/-??

BTW, you meter can read 1600 Mega Ohms?

My meter says MΩ which I took to mean Mega Ohms

I'll get right back on it when I get to the shop..

Thanx for the replies..

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

That might be a match, looks like it has the same part number: https://www.ebay.com/itm/4T-TCN550-C...cAAOSwzztdOxRt

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

That might be a match, looks like it has the same part number: https://www.ebay.com/itm/4T-TCN550-C...cAAOSwzztdOxRt

Yea, the one I have is a 1-C-7... I found one on EBAY, but want to confirm that the TCON will fix it.. On the other hand, it's only about $25..

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Looks like they both work, I thought they looked very similar: https://www.shopjimmy.com/tcl-4t-tcn...-con-board.htm

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Yea, I am guessing it's likely a firmware difference..

Just got to the shop, will test those MLCCs ..

Question, are the MLCCs ALL of the tan caps?? Or just the larger ones I marked??

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Probably all the ones that start with C.

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

OK, getting some different readings now..

With the + probe on the lower and the - probe on the upper, I get 7.5K +/-

With the - probe on the lower and the + probe on the upper, I get 10.05K +/-

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Probably all the ones that start with C.

That's a lot of probing..

Thanx

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Do you have an idea of what I am looking for??

Like a 0.0 reading means that cap is dead or something like that??

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

I think 0 is dead short and too low is bad too.

[Michale32086]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

OK... A probing I will go..

[nomoresonys]

Re: TCL 55US57 Bad Tcon Or Bad Panel Boards

Dog did it like this, he got pretty fancy and used both diode and ohm modes, the showoff, lol, I could use a pair of those Superman glasses he's got there: https://www.youtube.com/watch?v=jLd6QO7Z7m4