Replaced bulging caps, and pop... nothing

Collapse
X
 
  • Time
  • Show
Clear All
new posts

  • Trinite
    replied
    Re: Replaced bulging caps, and pop... nothing

    Show us a picture of the switchers and the diodes. Those are the other things that tend to go "pop". Also a complete pic of the underside of the board would help too, as there are a lot of SMD components on that side.

    Leave a comment:


  • Karstedt
    replied
    Re: Replaced bulging caps, and pop... nothing

    Now with pics of my masterless work. I circled the new caps, and the only joint that rally concerns me is the bottom one with the slight scorching around it (that was there before I got to it). I struggled with that joint.
    Attached Files

    Leave a comment:


  • Karstedt
    started a topic Replaced bulging caps, and pop... nothing

    Replaced bulging caps, and pop... nothing

    I have one of those va912b's with a bad power supply. I replaced 3 of the caps that were bulging, and when I plugged it pack in, I heard a pop (not an exploding cap) and nothing happened. Did I fry it with a bad joint or something? Or should I just replace the other caps too (except the big one).

Related Topics

Collapse

  • momaka
    HannStar Hanns-G HC194d LCD monitor repair
    by momaka
    Normally, I never post repairs this quick after I do them, because… I am usually very slow. But today, I’m making an exception here. Why? No idea. Perhaps only because the repair details are still “fresh” in my head… which is ironic, given this is a 16 year old monitor that hardly anyone will care about today. It is new to me, though. I picked it up last November from someone on my local Craigslist. It wasn’t very close to where I live, but was close to a family friend that I had to go visit anyways. So after watching the posting on Craigslist for a few weeks and seeing it getting...
    03-15-2023, 10:17 PM
  • zlr8r
    HP Probook 640 G5 - replaced blown components, getting power led, fan full, 5-flashes on CAPS Lock and NUM lock, black screen
    by zlr8r
    Hey guys, bit stumped with this laptop after replacing 2 blown components i.e., MP86493, MP2979A.

    To begin with, this laptop was dead-dead.

    Now with replaced (visibly) blown components, i do get some progress; after connecting battery or main cable;
    • am getting white power led
    • 5-long-flashes on CAPS Lock and NUM lock
    • then, fan full speed
    • CPU heats up some (smaller die PCH, does not)
    • always constant black screen no matter what's tried
    • no USB recognition
    • no HDMI output
    this is as far as I can get with it and not sure where to inspect next ?

    I tried...
    03-27-2024, 03:13 PM
  • cmlewis89
    LG 47LB5DF blown power supply board
    by cmlewis89
    Hi folks,

    I'm new to this forum. So my trusty 17-year-old LG 47" LCD recently died. As I was booting it up, I heard a hum followed by a loud bang, sounds of pieces flying around, and loss of power to the unit. Inspecting the PSU, I saw two obvious problems: a blown thermistor (bang + flung pieces) and a visibly bulging main cap. Inspecting as many components as I could with my Fluke MM, I diagnosed that the following components on the "hot side" of the board were also bad: one of the 2 main MOSFETs, main 8A fuse, small cap (25V 47uF) connected to main caps, and a blown...
    09-03-2024, 07:50 PM
  • bcstedt
    LG 42LB5D, 42LB5DF-UL, 2008-01, Power On Issue, Replaced PS Caps
    by bcstedt
    LG 42LB5D (42LB5DF-UL) from 2008-01, unit is in good shape and no obvious heat damage or cracked solder on the boards.

    Problem:
    On first power-up the power LED flashes green about 18x and then stays solid. No backlight or image is present. Click power button, wait 10s for a click and the LED turns red. Wait 1-2s and hit power again and maybe it'll power up fully after 6 green flashes. If it doesn't light up on the sixth flash then the cycle repeats.

    It seems that if the mainboard power is left on for a few minutes (solid green power, no backlight, no image)...
    01-18-2024, 01:03 PM
  • eryjus
    Heathkit IO-4205 Power Supply Caps
    by eryjus
    Hello,

    First, I am a complete noob with high voltage stuff. I'm learning, but I need help by someone looking over my shoulder.

    I recently came into posession of a Heathkit IO-4205 5MHz Dual Trace Oscilloscope. The documentation is copyright 1978. I'm told it works.

    I opened it up to check the caps before I applied power, and found the following black caps and wanted to know what they were. They are on the power supply board. I was able to read the name and model and came up with, "Nytronics 162J-1, 0.1uF, 20% tolerance, 2000VDC."
    ...
    05-10-2023, 11:21 AM
  • Loading...
  • No more items.
Working...