Sanyo DP42848 No Backlights

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • landyboy
    Badcaps Veteran
    • Apr 2013
    • 443
    • USA
    #1

    Sanyo DP42848 No Backlights

    Picked up a Sanyo DP42848. Set turns om and has sound. I can see a picture with the flashlight test. So it appears the backlights are not coming on. I have tested the PS and here is what I have:
    24V 23.89vdc
    SGND 0
    12v 12.09vdc
    SGND 0
    5v 4.99vdc
    SGND 0
    PSON 4.88

    Also have 23.87 volts on the 24v pins where the inverter board connects to the PS

    I noticed two very slightly bulged caps on the main board.
    Attached Files
    Tags: None
    • capkid
      Badcaps Legend
      • Oct 2010
      • 1339
      • United States
      #2
      Re: Sanyo DP42848 No Backlights

      I don't see the bulging caps on the main board. These TVs are notorious for bad CCFLs; I picked up one of these for free myself awhile back. I wouldn't touch Sanyo LCD TVs: https://www.badcaps.net/forum/showthread.php?t=23280
      Last edited by capkid; 06-23-2013, 07:47 PM.
      LG Plasma Mal-Discharge Correction Service

        Comment

        • kevinm34232
          Badcaps Legend
          • May 2012
          • 1884
          • USA
          #3
          Re: Sanyo DP42848 No Backlights

          Did you check 2 white 4A fuses on inverter board yet?

          Not sure if you can bypass a bad bulb in this design like in the this video, maybe someone else would know..

          https://www.youtube.com/watch?v=oE6K4xBVweA

            Comment

            • landyboy
              Badcaps Veteran
              • Apr 2013
              • 443
              • USA
              #4
              Re: Sanyo DP42848 No Backlights

              Kept searching the forum after I posted and found another thread. I thought I checked all the fuses but missed one on the main inverter board that was bad. Replaced and now it works!!

                Comment

                • landyboy
                  Badcaps Veteran
                  • Apr 2013
                  • 443
                  • USA
                  #5
                  Re: Sanyo DP42848 No Backlights

                  Kevin it was actually the small fuse marked 15 on the main inverter board.

                    Comment

                    • kevinm34232
                      Badcaps Legend
                      • May 2012
                      • 1884
                      • USA
                      #6
                      Re: Sanyo DP42848 No Backlights

                      OK, now run it for awhile before you put it back together to make sure no other underlying problem..

                        Comment

                        • landyboy
                          Badcaps Veteran
                          • Apr 2013
                          • 443
                          • USA
                          #7
                          Re: Sanyo DP42848 No Backlights

                          Will do thanks!

                            Comment

                            • budm
                              Badcaps Legend
                              • Feb 2010
                              • 40746
                              • USA
                              #8
                              Re: Sanyo DP42848 No Backlights

                              Very common failure for the CMO inverter board, the fuse is for powering the PWM IC.
                              Never stop learning
                              Basic LCD TV and Monitor troubleshooting guides.
                              http://www.badcaps.net/forum/showthr...956#post305956

                              Voltage Regulator (LDO) testing:
                              http://www.badcaps.net/forum/showthr...999#post300999

                              Inverter testing using old CFL:
                              http://www.badcaps.net/forum/showthr...er+testing+cfl

                              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                              http://s807.photobucket.com/user/budm/library/

                              TV Factory reset codes listing:
                              http://www.badcaps.net/forum/showthread.php?t=24809

                                Comment

                                Previous template Next

                                Related Topics

                                Collapse
                                • fharris1977
                                  Sanyo DP65E34 Backlights off after a 1-2 sec
                                  by fharris1977
                                  Hello. I have a Sanyo TV that had no backlights at first. I changed CS9 off the power supply and now the backlights will come on for a second or 2 and go right back off. I can see the image if I shine a flashlight in the screen. Anyone familiar with this particular model and problem, your help would be greatly appreciated. Thanks in advance....
                                  03-14-2023, 01:13 PM
                                • max789
                                  Samsung UE48H6410 replaced Mainboard but backlights doesnt go on
                                  by max789
                                  Hello, I have a problem with my Samsung UE48H6410SSXZG with the main board BN41-02156A and the power board BN44-00709A. Everything seemed like this, the TV could no longer be switched on, the standby LED always flashed 5x2 times. Backlight was off and no sound from TV. Also made the flashlight test and there was no picture.

                                  I made the following tests:
                                  1. Disconnected the main board from Power Board = backlight works.
                                  2. Connected the main board and disconnected the T-Con = backlights does not work.

                                  So I ordered a main board from Ebay also BN41-02156A but from...
                                  01-18-2024, 06:56 AM
                                • bpcannan
                                  VIZIO M557-G0: Backlights or ???
                                  by bpcannan
                                  'Morning,
                                  I get sound and picture when powering on the TV and its stays that EXCEPT that the left half of the screen will dim every few seconds then return to normal while the right side of the screen performs as designed.

                                  Did the soft and hard reset options pulling the plug, using the reet option in the vizio menu to no avail.

                                  I checked the mainboard - found some popped capacitors so replaced it - but that did not change the situation.

                                  I checked the t-con board. It is getting good power. Then I removed one ribbon cable to see if I could isolate...
                                  10-29-2023, 06:36 AM
                                • jesterace
                                  Samsung UE49MU6400 acts dead until disconnecting backlights, then works.
                                  by jesterace
                                  Hi everyone I have this TV which was dead one day when I tried to turn it on. I've had the cover off and there was just a pulsating/electrical clicking/ticking noise from the PSU. I disconnected the mainboard as sometimes this works to just fire it up with backlights on? That didn't help. Same noise. Then I disconnected the backlight cable from the PSU and the TV came alive. It appeared to respond to the remote and i'm pretty sure it's fully operational when there is no backlight connected.

                                  However, I am in a dilemma.

                                  I tested the backlight outputs with the lights disconnected...
                                  10-20-2024, 10:15 AM
                                • jimbofz
                                  toshiba 65ul2163 dbl no backlights NOT BACKLIGHTS?
                                  by jimbofz
                                  Hi this vestel 65in tv had classic no backlights ,so nothing new there!
                                  tested with b/l tester and the b/l seemed to be fine
                                  so investigated psu 17ips72 (on this 65inch there are 3 fets and control iv type DB83630P)
                                  did a thorough check on b/l circuit all ok .
                                  When i tried again with b/l tester all ok .but then when i reinstalled psu all worked fine ,
                                  could there be a component on psu that is causing the protection mode to stop b/l
                                  .maybee causing it to be too sensitive?
                                  it seems to me if the b/l have been on with my tester ,within a couple of minutes...
                                  06-07-2025, 10:11 AM
                                • Loading...
                                • No more items.
                                Working...