Announcement

Collapse
No announcement yet.

Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Maklaud
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    I think some of the bad transformers. (I mean inside spark or closes).

    Leave a comment:


  • CapLeaker
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    that too.

    Leave a comment:


  • budm
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    I wonder about the condition of those 4 filter caps on that inverter board.

    Leave a comment:


  • CapLeaker
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    maybe one of those IC's are damaged that sit in front of each transformer.
    http://www.shopjimmy.com/cmo-27-d008...-inverter.htm#

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    I have a new inverter board and the tv is working now for the last 2 days.
    I measures all the 8 transf. on both boards and they are the same readings.

    Leave a comment:


  • Maklaud
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    http://english.electronica-pt.com/lcd-repair?p=OZ964

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Hi,resolder all the pins on all 8 transformers and the tv worked for about 30-40 min and now has the same fault.
    Dim Voltage =3.291v before and after backlight turns off
    BL-ON ??/I could not found .is BR1 the same ?
    BR1=2.070v
    How I block the protection OZ964GN ?

    Leave a comment:


  • Maklaud
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Try to block protection OZ964GN. Then try to remove one of eight transformers. And one by one test.


    And by the way...

    Originally posted by budm View Post
    The BL-ON and the Dim control signals are still present when the lights go out?
    Where's your answer?
    Dim Voltage = ?
    BL-ON = ?

    I had a case when the backlight is blinked and inverter noise due to DIM (The problem was in the EEPROM on the main board)
    Last edited by Maklaud; 09-21-2015, 05:10 PM.

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    I have tested with the white screen and looks absolute fine with all the ccfl light up.
    I will resolder all the transformers pins and see what happens .
    Attached Files

    Leave a comment:


  • budm
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Well, try that white screen test in the darkened room , may be it will be on long enough for you to see if all the lamps are on.
    Attached Files
    Last edited by budm; 09-21-2015, 03:29 PM.

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Panel number is V315B1 -L07
    When tv go off buzzing noise could be heard from the inverter and the screen is black no light at all.Photos attached when tv working and with the black screen sound fine.
    Attached Files

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Originally posted by budm View Post
    BTW, you are running the Inverter board without the shielding in place and
    All the screws and the metal shield in place all the time when tv was powered on.

    Leave a comment:


  • budm
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    BTW, you are running the Inverter board without the shielding in place and do not see any mounting screws for the inverter board to GND the board to the chassis.
    Do you have the LCD panel model number?
    You may have lamps problem at this point if everything checked out fine on the inverter board.
    May be you can try running video with the white back ground then you may be able to see if one of the lamps is not on, you will see horizontal gray bar where the lamp is not lit.
    Last edited by budm; 09-21-2015, 02:50 PM.

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Reconnected the inverter to the tv and after reading all values with the picture on and with the picture off all readings from the main board remains the same.
    Attached Files

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Originally posted by kc8adu View Post
    no caps in series so measure/compare at the ccfl connector.
    very likely you have a bad transformer.common on those inverters.
    could also be a bad lamp.
    Thank,between the connector the measurements are nearly the same 2.043k

    Leave a comment:


  • budm
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    The BL-ON and the Dim control signals are still present when the lights go out?

    Leave a comment:


  • vinceroger69
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    what voltages change? on the power supply when the picture goes off.

    Leave a comment:


  • matyka
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    Thanks,already measured that way and I have around 1.068k on all 8 of them.
    To be honest I don't think are the transformers who have failed on this inverter

    Leave a comment:


  • vinceroger69
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    http://www.lcdparts.net/TransformerD...ProductID=3497

    Leave a comment:


  • kc8adu
    replied
    Re: Lg 32LC46 Backlight cuts out after tv on for 3-4 sec

    no caps in series so measure/compare at the ccfl connector.
    very likely you have a bad transformer.common on those inverters.
    could also be a bad lamp.

    Leave a comment:

Working...
X