TCL 55S451 Blank screen

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  • x_orange90_x
    replied
    Originally posted by nomoresonys
    Capital M for megaohms, small m for milliohms.
    Thanks for the clarification. I used my other meter and it displayed the capital M as well, but I did notice the readings started out in K ohm and climbed up into the M range. Is it okay then that they are reading that way or should I suspect an issue with one or more?

    I still need to get a picture of the lines I blocked off on the ribbon. I didn't get a chance to do it last night.

    Leave a comment:


  • nomoresonys
    replied
    Capital M for megaohms, small m for milliohms.

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    And how do you determine that it shows Om, kOm, MOm?
    I looked at the owners manual online and it doesn't help. That's all I know is it says ex. 5.00 M ohm

    I thought that if they read anything other than OL they would be suspect and one bad can make others read bad when they're not. I have another older meter I try and see if it's different.

    Leave a comment:


  • lotas
    replied
    And how do you determine that it shows Om, kOm, MOm?

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas

    I can't understand what resistance is, what is it in megaohms, milliohms...?
    Here is my meter:

    https://www.innova.com/products/hand...10-megohm-3306

    It's an auto ranging 10 MegOhm meter. It's "M" not "m" on my display, don't know if that helps.

    Leave a comment:


  • lotas
    replied
    Originally posted by x_orange90_x
    Attached is a picture of the readings I got, going from the left side of the strip to the right. The caps not listed read OL. I'm guessing probably only one cap is bad but pulling down the others? I notice that all that read low are positioned in the middle of the strip instead of near the top where most of the others are.
    I can’t understand what resistance is, what is it in megaohms, milliohms...?

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    Well then, compare with the working strip what resistance they have on the capacitors, you just need to disconnect the cables going to the t-con. You may have masked more contacts than required, and now power is not supplied to the non-working strip, but I don’t see what you masked there, maybe half of the cable is masked there.
    You reminded me just now, I did check them on the working side and they all read OL.
    Last edited by x_orange90_x; 12-10-2023, 01:17 PM.

    Leave a comment:


  • lotas
    replied
    Well then, compare with the working strip what resistance they have on the capacitors, you just need to disconnect the cables going to the t-con. You may have masked more contacts than required, and now power is not supplied to the non-working strip, but I don’t see what you masked there, maybe half of the cable is masked there.

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    If none of the capacitors have low resistance (in Om), then they are fine, show where you masked the contacts.
    Are those readings normal then despite the others reading OL?

    I will try to get you a picture of what I masked off. It was on the main board side of the ribbon but that should't matter since I pinned the traces for continuity.

    Leave a comment:


  • lotas
    replied
    If none of the capacitors have low resistance (in Om), then they are fine, show where you masked the contacts.

    Leave a comment:


  • x_orange90_x
    replied
    Attached is a picture of the readings I got, going from the left side of the strip to the right. The caps not listed read OL. I'm guessing probably only one cap is bad but pulling down the others? I notice that all that read low are positioned in the middle of the strip instead of near the top where most of the others are.
    Attached Files

    if you find these attachements useful please consider making a small donation to the site

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    Yes, now you can see that there are no protective diode assemblies here; you checked the ceramic capacitors for low resistance with the cable disconnected.
    I don't think it was unplugged. I can recheck them.

    Leave a comment:


  • lotas
    replied
    Yes, now you can see that there are no protective diode assemblies here; you checked the ceramic capacitors for low resistance with the cable disconnected.

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    Yes, I’m interested in the very edge of this bar, what components are located on it.
    Here are the pictures. The one with the black tape is the end you asked about.
    Attached Files

    if you find these attachements useful please consider making a small donation to the site

    Leave a comment:


  • lotas
    replied
    Yes, I’m interested in the very edge of this bar, what components are located on it.

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    And you can see this entire bar; this chip is a spi flash.
    I will get a photo of the whole bar later when I get home. Is there something specific you're looking for? I can try to get a close up of it if so.

    Leave a comment:


  • lotas
    replied
    And you can see this entire bar; this chip is a spi flash.

    Leave a comment:


  • x_orange90_x
    replied
    Originally posted by lotas
    Post a photo in full, in good quality, of the faulty buffer strip and your photo, which contacts you masked.
    Here's some photos of that side. I need to get another of the outside edge but this is a start. Also, I used my multimeter on continuity and touched one probe to CKV test point and the other to the pins on the ribbon. I determined it's lines 4-12 and blocked those off, that's how I got the grey screen on that side.

    I also attached a screenshot of the pinout for that chip.
    Attached Files

    if you find these attachements useful please consider making a small donation to the site

    Leave a comment:


  • lotas
    replied
    Post a photo in full, in good quality, of the faulty buffer strip and your photo, which contacts you masked.

    Leave a comment:


  • x_orange90_x
    replied
    Update! I disconnected the right side ribbon and got an image on the left side! I did this probably a dozen times before and didn't get an image but now I do. I checked all of the resistors on that sides scaler and they all tested good, and so did the caps. I pinned out the CKV lines and blocked them off but I just get a gray image on that side and the left side is fine. Is there something else that needs to be taped off along with the clock lines?
    Attached Files

    if you find these attachements useful please consider making a small donation to the site

    Leave a comment:

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