LG EAY60968801 Power Supply Unit
There's heaps of threads on these type of PSU including other variants all with similar issues.
I've tried looking for similar threads to mine but never see a fix. If you've got the common failure of open cct resistors or bad IC you're laughing.
I also have the HD model PSU LG EAY60968701 Power Supply Unit which was running fine until I started borrowing parts and poking around and it too has the exact same symptoms, so I've spiked something but can't find it.
Here's what I can tell you based on EAY60968801 .
Firstly I've set it up for testing minus a load which is not an issue for what I want to do.
Apply power, 2 relay clicks
Stdby, M17V , M5v are good, ACDET is good, Error DET is good
No Va, or VS
Relays unlatch, denergises, pause then repeat 2 clicks , reading s as above and continually does this.
If it's fitted, 3 of these cycles then quits. Assume the mainboard says enough is enough and stops the cycle.
No open cct high wattage resistors
No shorted ICs or Transistors evident
Resistor network commonly identified as faulty good and even rebuilt
All solders are good
all transformers good
No obvious shorted diodes, ZD301 was damaged through the fault finding and went short , replaced
Micro controller, IBR chip, two driver ICs, and optos all swapped out and fitted to another working board, confirmed all good.
Surface resitors appear ok, have compared measurements to good board and seem comparable.
have tried using Paulsetf's cct diagram but stumped.
There are a number of surface transistors with inbuilt resistors, not sure how you know if they're bad
Images are stock images hoping someone can work out the cct
There's heaps of threads on these type of PSU including other variants all with similar issues.
I've tried looking for similar threads to mine but never see a fix. If you've got the common failure of open cct resistors or bad IC you're laughing.
I also have the HD model PSU LG EAY60968701 Power Supply Unit which was running fine until I started borrowing parts and poking around and it too has the exact same symptoms, so I've spiked something but can't find it.
Here's what I can tell you based on EAY60968801 .
Firstly I've set it up for testing minus a load which is not an issue for what I want to do.
Apply power, 2 relay clicks
Stdby, M17V , M5v are good, ACDET is good, Error DET is good
No Va, or VS
Relays unlatch, denergises, pause then repeat 2 clicks , reading s as above and continually does this.
If it's fitted, 3 of these cycles then quits. Assume the mainboard says enough is enough and stops the cycle.
No open cct high wattage resistors
No shorted ICs or Transistors evident
Resistor network commonly identified as faulty good and even rebuilt
All solders are good
all transformers good
No obvious shorted diodes, ZD301 was damaged through the fault finding and went short , replaced
Micro controller, IBR chip, two driver ICs, and optos all swapped out and fitted to another working board, confirmed all good.
Surface resitors appear ok, have compared measurements to good board and seem comparable.
have tried using Paulsetf's cct diagram but stumped.
There are a number of surface transistors with inbuilt resistors, not sure how you know if they're bad
Images are stock images hoping someone can work out the cct
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