Hi there !
I would like to thank you first for this great forum, I learn a lot here on LCD repair !
I recently found a dead 19" Hyundai L90D+ that I really would like to fix and I think I'm getting closer to this.
Here is what's the problem : just after plug in the power cord, the blue power led turns on. About 5 seconds later, this same led quickly turns to orange and everything shutdown like if a short has come (I can also hear a tick at this time). So, this process restart and loop forever. No Backlight at all.
Looking to the power/inverter board doesn't show me bulged caps, and anyway it looks like more a MOSFET issue.
I disconnected it from the logic board, the ticking stop and I get a good 12V and 5V at pins header without shutdown.
Then, I hooked SLP to 5V and the backlight starting to flash.
This drive me to the solder side of the board where I can find two dual NP mosfet (U4 and U5) named APM9932 (datasheet here ). Looking closer, I can also see a damaged smd capacitor just nearby U5 (C23). So I suspect something in that area to be the failure.
Since I cannot find service manual for this monitor, I don't really know what value is C23 nor what kind of mosfet can substitute these APM9932 (can't find them on Digikey or Mouser). And anyway, I'm not an hardcore mosfet calculator.... :p So I need your help on this point !
Am I right on what I have done ? Any advices else ?
Many thanks in advance !
I would like to thank you first for this great forum, I learn a lot here on LCD repair !
I recently found a dead 19" Hyundai L90D+ that I really would like to fix and I think I'm getting closer to this.
Here is what's the problem : just after plug in the power cord, the blue power led turns on. About 5 seconds later, this same led quickly turns to orange and everything shutdown like if a short has come (I can also hear a tick at this time). So, this process restart and loop forever. No Backlight at all.
Looking to the power/inverter board doesn't show me bulged caps, and anyway it looks like more a MOSFET issue.
I disconnected it from the logic board, the ticking stop and I get a good 12V and 5V at pins header without shutdown.
Then, I hooked SLP to 5V and the backlight starting to flash.
This drive me to the solder side of the board where I can find two dual NP mosfet (U4 and U5) named APM9932 (datasheet here ). Looking closer, I can also see a damaged smd capacitor just nearby U5 (C23). So I suspect something in that area to be the failure.
Since I cannot find service manual for this monitor, I don't really know what value is C23 nor what kind of mosfet can substitute these APM9932 (can't find them on Digikey or Mouser). And anyway, I'm not an hardcore mosfet calculator.... :p So I need your help on this point !
Am I right on what I have done ? Any advices else ?
Many thanks in advance !
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