Samsung LED TV Takes Ages for Picture / Display to Warm up - Sound Works Straight Away

Hoju on 18/06/2018 - 14:33
Last edited 18/06/2018 - 15:19

I know there are some exceptionally clever electronics folk here. One day I hope to have some space to tinker with a soldering iron. Until then I hope someone can advise

I have a samsung smart led tv, probably about 2012

Edit : sorry it’s a Samsung ua32es6200

Recently it started taking a couple of minutes before the display would come on. The sound would come on as normal and eventually the picture would show. During this time no menu can be displayed but channels can be changed.

Today it probably took about 20 mins. Once it’s on, if you turn it off for a short while it will turn back on immediately as normal.

A google search suggests maybe a capacitor of some sort, although the known issue seems to involve a capacitor clicking in some way, which this does not do.

I would hate to ditch the tv, and if it died completely I wouldn’t mind trying to have a look for any bulging capacitors or other signs of failure.

If anyone had any clever thoughts it would be much appreciated - I’m scared to turn it off at this stage, though I don’t know if this is actually putting greater stress on any remaining working parts!

Electrical & Electronics

Comments

  • Cartman2530 on 18/06/2018 - 14:40

    A model number of the tv would help, at the very least.

    • Hoju on 18/06/2018 - 15:03

      Sorry it’s a Samsung ua32es6200

  • Cartman2530 on 18/06/2018 - 15:13
    +1

    If you turn it on in a darkened room is there a difference in the screen when its off vs on, ie can you see backlight bleed but nothing on the screen or is it still a dark the same as if it were off?

    This would narrow down the problem to the backlight circuit or the LCD TCON/Processor circuits.

    • Hoju on 18/06/2018 - 15:20

      Thanks I’ll try tonight !

  • HighAndDry on 18/06/2018 - 15:14

    Eh. Any potential fix would likely require tinkering with the circuit board of the TV which would involve taking the TV apart and, well, soldering.

    If you post the model number, may be we can see if anyone else online has had the same issues and if there's a less complicated solution.

    • Cartman2530 on 18/06/2018 - 15:20
      +1

      Usually you would just find a replacement board of the one that is faulty. Fairly easy to find on ebay or an online store like shopjimmy.com.

      Troubleshooting board level problems and replacing components is not really possible if you don't have any electronics skills, but swapping a whole board over is possible if one takes their time.

      • HighAndDry on 18/06/2018 - 15:31

        Actually that's a good point, and on second thought if there's sound it's likely an LED backlight issue more than it would be a board issue.

  • Hoju on 18/06/2018 - 15:36

    What’s odd is that it works perfectly without a flicker or any issues once it’s ‘warmed up’

    I haven’t soldered for about 20 years but I can repair the odd iPhone issue eg dock and screen without problems so hopefully if there’s a replaceable part I could do it. Just need to find out what!

    • Cartman2530 on 18/06/2018 - 15:56
      +1

      I remember there was a run of LG tvs years ago that cracked solder balls on the BGA that output video to the lcd, once the board heated up enough they made contact and it worked. The problem sounds similar to yours in which case the solution was to reflow the board in an oven to reflow the solder.
      If that didn't work the next thing was to get another board.

      But find out first whether it is the backlight or the processing side. Then you can go from there to narrow down the exact area that has a problem.

      If you have some electronics experience then i think you should be fine swapping boards over, the hardest part these days is taking the tv apart!

  • Hoju on 18/06/2018 - 18:32

    Bother.
    Turned it back on this evening in a dark room. Absolutely nothing from the screen at all.
    Have left it on 20mins so far and the picture hasn’t appeared.
    Argh technology

    • Cartman2530 on 18/06/2018 - 21:43
      +1

      Ok, so the led backlight seems to be the culprit. Shine a torch on the screen and see if the LCD itself is working, you should see some movement of the picture that should be on the screen. That means the LCD is good and so is the video output/processing side of the tv.

      I've seen tvs where a led in the strip is faulty and causes the symptoms that you are having. Since they are all in series there is a high voltage across the whole led strip. The led that is open eventually conducts due to the high voltage across it which will turn the strip on.

      You will have to disassemble the tv and check each led in the strip with a multimeter on the diode range. the multimeter needs to have a high enough test voltage for the led forward voltage, which is roughly anywhere from 2.5V to 4.5V. The faulty one will be open testing in both directions.

      If a led is faulty, thats the easy part. The hard part will be replacing it. If you are lucky there may be a tv the same model of yours with a smashed screen. You could swap over the led strip to yours and you are good to go.

      The other thing you could do is short the faulty led out and it should work then. The only problem with this is there would be a brightness variation where the missing led is.

      Its not an easy process but if you understand what I've said then you should be fine if you take your time.

      TL:DR Led in the backlight strip may be faulty, check with a multimeter and confirm. Hope this helps.

      • Hoju on 18/06/2018 - 22:11

        Wow that’s really handy thank you.
        Amazingly yes, with a torch I can just make out the moving images of the tv behind the screen.
        So it seems it’s likely just as suggested.

        I’m keen to have a crack at fixing it. I have no idea what I’m looking for in an led strip but I’m sure I can find a video online :)

        Thanks again!

  • Hoju on 19/06/2018 - 07:09

    Gee it does look like disassembling the tv is the hard bit

    This Guy has a simple way of testing. Connect a few 9v batteries in series to make 27v and connect to the + and - of each strip to see if they lift up

    Don’t have a multimeter (yet)

    • Cartman2530 on 19/06/2018 - 08:31
      +1

      That might work but without any current limiting there would be a good chance of burning out the whole led strip.

      You really need a multimeter and test the voltage on the output of the power board connector that feeds the led strip. Most TVs these days run upwards of 200V across the led strip due to so many leds being in series.

      I would test the voltage and double check there is actually a voltage there. If there is, its the led strip. If not, its the power board.
      Also, don't do this with a cheap multimeter, try and get a quality one. The $20 one from bunnings won't cut it and could be dangerous in this instance.

      BE EXTREMELY CAREFUL though as there is high voltage (380V DC) on the power board! If you don't feel confident working around high voltage and the mains, I would not attempt it, as the risk of injury is high.
      If you know of anyone that has electrical experience with high voltage mains powered devices, I would definitely ask you to let them do it instead.

  • gazza the great on 19/06/2018 - 19:33

    Any news on the tv repair? This is like watching The Bold and The Beautiful.

    • Hoju on 19/06/2018 - 20:09

      Need to get hold of a multimeter!
      The season cliff hanger will be can he or can he not actually open the damn tv

      • Cartman2530 on 20/06/2018 - 12:58
        +1

        All I can say is don't force it open, if the back cover doesn't come easily, look for a screw you have missed.

  • Cartman2530 on 25/06/2018 - 18:13

    Any news on this? Did you get it apart and test it?

    • Hoju on 05/07/2018 - 04:42

      Argh sorry missed the notification / lack of - took it off the wall and never got a chance to take the back off.
      Little bit scared I'm going to completely destroy it, not sure if it would be worth something for parts now as it is before I try my hand at fixing aka destroying it!

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