32" Dynex DXL3210A Won't Power On

Collapse
X
 
  • Time
  • Show
Clear All
new posts

  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    yeah this is the problem I mentioned in post 64, having trouble trying to figure out where the P_ON trace leads

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    Nope there doesnt seem to be a chip near there on the bottom.

    The resistor you mentioned in post 67, R680, when I measure the left side pin of it, I get a reading of 5.30V and 0V if i measure the right side. Would it still be the same trace, since P_ON measures 3.31V?
    bah, I guess it is not!

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Nope there doesnt seem to be a chip near there on the bottom.

    The resistor you mentioned in post 67, R680, when I measure the left side pin of it, I get a reading of 5.30V and 0V if i measure the right side. Would it still be the same trace, since P_ON measures 3.06V?
    Last edited by tieny; 07-23-2012, 02:10 PM.

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    actually my mistakes it continues to follow to more resistors.
    Hm, and where do those go? Is there a chip on the bottom of the board?

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    actually my mistakes it continues to follow to more resistors.
    Attached Files

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    It leads to X102 and to the back of the main board to some resistors connected to the 5V pin. Following the trace leds to a dead end.
    in the third pic, what does the trace goto on the other side?

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    It leads to X102 and to the back of the main board to some resistors connected to the 5V pin. Following the trace leds to a dead end.
    Attached Files

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Where and what does this trace lead to? (marked in yellow)
    Attached Files

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    It reads 81R, When I put both probes together I get 0.04 ohms.
    Ok, you meter is calibrated ok, and the 81R means the resistor is 81 ohms.

    Seems almost like its supposed to be a pull-down resistor, but the chip that drives it seems to be shorted. 81 ohms is also low resistance for a pull-down/up resistor.
    Last edited by ben7; 07-23-2012, 01:35 PM.

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    It reads 81R, When I put both probes together I get 0.04 ohms.

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    Measuring from the P_ON pin and the resistor (Red probe on P_ON and black probe on the resistors pin), I get 4.72 ohms on the left side and 5.36 ohms on the right.
    Hm. What number is written on the resistor?

    Is your meter calibrated? (put both probes together, it should measure nearly 0 ohms)

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Measuring from the P_ON pin and the resistor (Red probe on P_ON and black probe on the resistors pin), I get 4.72 ohms on the left side and 5.36 ohms on the right.

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    Heres a better picture of the connector.
    Thanks

    See the resistor marked R680 next to the header?

    Which pin of the resistor is connected to the P_ON pin?

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Heres a better picture of the connector.
    Attached Files

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    I tried tracing the pin back to any connecting components using the continuity function on my multimeter but i couldnt seem to find any before. Ill give it another try once i get home. Theres a closeup photo of the pin and nearby components in post 59 if you have any suggestions.
    The picture is on the wrong side of the connector though, I cant see where any of the traces go. It seems like the P_ON goes to an empty spot where a chip should be. Not saying the chip should be there though, some models exclude certain circuits, so they leave the component spaces blank.

    And Im not talking about taking a picture on the back side of the board, there are no traces there to track from one of your other photos.

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    I tried tracing the pin back to any connecting components using the continuity function on my multimeter but i couldnt seem to find any before. Ill give it another try once i get home. Theres a closeup photo of the pin and nearby components in post 59 if you have any suggestions.

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    I dont think the PSU is bad, since all the output voltages appear on it. The problem is that once the tv is plugged in, the p-on voltages appears consistently. As before when the tv worked, the p-on voltage read 0v until i pressed the power and it rose to 3.3v. As budm suggested it could be a main board problem that is sending out the signal to the psu too early. Also the voltages on the 24v going to the inverter board is appearing too early.
    Seems like something on the mainboard has its output stuck on, I would trace back the P_ON signal to the chip it comes from.

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    I dont think the PSU is bad, since all the output voltages appear on it. The problem is that once the tv is plugged in, the p-on voltages appears consistently. As before when the tv worked, the p-on voltage read 0v until i pressed the power and it rose to 3.3v. As budm suggested it could be a main board problem that is sending out the signal to the psu too early. Also the voltages on the 24v going to the inverter board is appearing too early.

    Leave a comment:


  • ben7
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    Originally posted by tieny
    What components on the main board are simple to test?
    Im sorry, but what is the problem again? Have you actually figured out that the PSU is bad?

    You can also check the mosfets on the primary side, and on the transformer, you can check to see if any windings are open-circuit.

    Leave a comment:


  • tieny
    replied
    Re: 32" Dynex DXL3210A Won't Power On

    What components on the main board are simple to test?

    Leave a comment:

Related Topics

Collapse

  • GLISIT
    Asus Probook P5440UF-XB74 power issue
    by GLISIT
    Hi all,

    TL;DR - this laptop is driving me nuts with the oddball power-related behaviors. Appreciate any insight you can provide!


    I'm experiencing a power issue on an Asus Probook P5440UF-XB74. Although I've worked with electronics and computers for decades, this is my first attempt at getting into motherboard-level component troubleshooting. Any help the community can provide is greatly appreciated!

    A few weeks ago I was using the laptop (on battery power) for a Zoom meeting. The battery was running very low (long meeting) but I wasn't worried about...
    01-16-2025, 02:29 PM
  • sam_sam_sam
    Desoldering gun station modified to use a 18 volt @ 20 amp switching power supply
    by sam_sam_sam
    I have wanting to do this project for quite sometime now and I finally found a switching power supply that will work on this desoldering gun station ZD-915 that the original switching power supply took a shit and just was not worth trying to fix it because this switching power is not quite big enough to handle the heater element and the vacuum pump

    One note when I tested the switching power supply and the voltage control board I noticed that this desoldering gun heat up much faster than the original switching power supply which I was really surprised by to the point that I might buy...
    03-31-2024, 02:12 PM
  • SkishyIshy
    Sony Bravia XBR-65x900f: No Power, No Standby-light - however 3.3v STBY is present
    by SkishyIshy
    Hey All,

    I have a Sony 65x900f that I purchased cheap because of a no-power issue.
    I assumed that because there is no standby light visible, it would be an easy fix - however upon opening up of the unit I can confirm that the 3v3 standby voltage is making it's way from the power supply to the main board. I'm a little confused as to why there is no standby light.

    I am firstly wondering if anyone has this model of TV, or has worked on one and can give me some insight. I have tried to find a service manual for this model, to no avail - and would really appreciate...
    03-17-2021, 11:44 AM
  • AleMonti
    LG 55EG910V - no power and no standby light
    by AleMonti
    Hi everyone,
    I'm trying to troubleshoot and repair this old LG OLED curved TV, model 55EG910V.
    I did some basic troubleshooting and reviewed most related posts here, but I wasn't able to isolate the issue.

    The TV shut itself off during playback and never came back to life - the standby light remains off. My dad claims that it has happened a few times in the past but the issue resolved itself after some time. Not this one.

    After checking the basics I did the following:
    • I measured all voltages and as expected the only active supply is the 3.5V standby. It
    ...
    11-04-2024, 05:02 PM
  • noinimod
    Sony 55X900E no standby light, no power. Replaced mainboard already
    by noinimod
    No standby red light, nothing
    This Sony has a separate AC->DC power adapter supplying 19.5V to the TV power board (JK3)



    Disconnected JK3 power board from main board, checked voltages on all the pin outs

    At a few pins I can see the power supply providing 19.5V to the main board



    Based on the service manual triage.. it seems to be pointing towards the power board (JK3) being the most possible culprit


    LED light turns on when I disconnect LED driver board ribbon from mainboard (so i thought it is the mainboard,...
    12-22-2021, 12:58 AM
  • Loading...
  • No more items.
Working...