HANNS-G HH251 2 seconds to black problem

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • sixstringartist
    Member
    • May 2012
    • 18
    • USA

    #1

    HANNS-G HH251 2 seconds to black problem

    Im troubleshooting the above monitor for a 2 second to black issue. Upon inspection of the power board, there were no obvious signs of bad caps but I replaced all of them anyway (except the 400v 120uF filter). Im attempting to determine if the problem is coming from a bad ccfl, inverter or something else. Ive tested all fuses on the power board and the IC206 which I thought was a transistor but after pulling the datasheet it appears to be a programmable shunt regulator? Im not familiar with how to test this.

    Ive read up on how to test for a bad CCFL but Im not sure I really understand it. My CCFLS do not appear to light up without having both connectors on a given inverter populated by a bulb. Is that because the oscillator needs both sides there to fire? If I replace all 4 ccfls with a known good set, the behavior appears to be the same. What should I do to continue troubleshooting? When should I start caring about whats happening on the logic board?

    https://imgur.com/a/7dVgSwZ
  • sixstringartist
    Member
    • May 2012
    • 18
    • USA

    #2
    Re: HANNS-G HH251 2 seconds to black problem

    Attaching photos
    Attached Files

    Comment

    • sixstringartist
      Member
      • May 2012
      • 18
      • USA

      #3
      Re: HANNS-G HH251 2 seconds to black problem

      Disregard this post for now. My testing after recapping the board may have been faulty. It appears to be working now and Im going to continue monitoring it.

      Comment

      Related Topics

      Collapse

      • ttmi100x
        HANNSG Hi221 -- 2 secs to black feat. CCFL flicker & "burn" marks on power board
        by ttmi100x
        Greetings everyone,


        I have a HANNSG Hi221 monitor that exhibits two seconds to black issues (backlight goes off, display is still on as confirmed by shining a flashlight on it) with some additional oddities...


        The monitor failed on me with a standard "2 seconds to black" some time ago prompting me to initially replace most of the electrolytic capacitors (some of them were bulging/leaking).
        Things kinda sorta worked for a night, then the problem returned along with some flickering and "buzzing" noises.

        Upon closer inspection...
        07-31-2024, 06:36 PM
      • redwire
        Onkyo TX-SR607 HDMI problem showing a black screen intermittently
        by redwire
        Onkyo TX-SR607 HDMI problem showing a black screen intermittently, audio was OK.
        It would usually cut out a few minutes after power on, for maybe 1 minute then work OK, then cut out and go to black again. Or fade out to sparkles and noisy video.

        Well known is these boards need recapping and there is a strange mix of parts on both sides of the board.

        The bottom of the board has 100uF 4V (5.3*5.3mm, qty 5) and 220uF 4V (6.6*6.6mm, qty 5).
        Per the service bulletin, an issue is the Toshiba LDO's want low ESR for stability so I went with 100uF 6.3V polymer...
        11-16-2023, 08:56 PM
      • ChIck3n
        Dell u2311h 20000 seconds to black issue
        by ChIck3n
        So I've had this monitor for probably a decade now, and it's finally starting to fail. Began with a little sporadic flickering, then eventually started going black (power LED stays blue, can still see image on screen with flashlight). A power on/off fixes it for a bit, but then it happens again. Once it got to the point I was dealing with this every few minutes, I opened it up and just replaced all the caps (minus the big one) on the power board with new Panasonic ones. All the old caps tested fine on an ESR meter, and this worked for 5 days. But the screen just went black again today, so...
        09-09-2024, 11:44 AM
      • Long AMD
        Acer AL1916W - Two seconds to black - Voltage regulator problem?
        by Long AMD
        Hello all. Excellent forum you have here - it has already been a great help to me. I am posting the details of my situation before I go and start buying parts to see what suggestions the great minds here may have on diagnostics or otherwise.

        I have an Acer AL1916W monitor which has recently failed in the following way: the screen comes on at power on, but after a couple seconds the screen goes black. Using a flashlight, I can easily verify the LCD is fine but there is simply no backlight.

        The power supply board is of the type ILPI-025 Rev C (Date of manufacture was...
        09-13-2020, 05:59 PM
      • DrankinSAW
        LG 37LG5020 and the tale of 2 seconds to black.
        by DrankinSAW
        I bought an LG 37LG5020 with a very strange issue.. it turns on, the display looks fine, but still, after 2 seconds, the TV shuts the backlight off..

        However, if i leave it plugged in for 20-40min.. the time it takes to shutdown the backlight, doubles (to 4 seconds)..

        I bought a new inverter, set to arrive on December 13th
        11-22-2023, 01:10 PM
      • Loading...
      • No more items.
      Working...