Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashlight

[carloroma63]

Re: Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashl

Hi all,
I'm too trying to fix a black screen on my monitor, which use DAC-19M008 power supply
I've read all previous post and none helped me to fix the problem.
My situation is the following:
- Power source on C200 cap is about 20V
- Voltage on pin 15 and 16 follow as described on https://www.badcaps.net/forum/showpo...89&postcount=4
- Voltage on pin 8 follow the Enable signal.
- Voltage on pin 5 and 12 is 5 V for some seconds at startup, then goes to zero
- voltage on pin 15 and 16 (output vs high mosfet) is fixed to 20V. At startup, after few seconds, oscillosope show a waveform with a short (less then 10 mS ) brust, from 20 to 16V, then stop and again goes to +20V
- voltage on pin 1 and 3 (output vs low mosfet) are fixed to 0.
- no fuse broken
- some capacitors appears to be swollen, but voltages are Ok.
- mosfet look to be NOT in short
- continuity of output trasformer seems ok (about 750 Ohm on both Secondary, near to zero on Primary)

Before try to replace the OZ9910, it isn't easy to find it in short time, someone can tell me if the waveform on pin 15 and 16 are normal during startup?

Thanks

Carlo

[carloroma63]

Re: Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashl

Addendum: With oscilloscope, I checked pin5 oscillator. At power on or after Screen Wakeup, it starts from 0V, then start to oscillate at about 3 Khz for few milliseconds ( about 20) then goes fixed to 5V.
Tomorrow I'go to buy a OZ9910....

[carloroma63]

Re: Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashl

Addendum: With oscilloscope, I checked pin5 oscillator. At power on or after Screen Wakeup, it starts from 0V, then start to oscillate at about 3 Khz for few milliseconds ( about 20) then goes fixed to 5V.
Tomorrow I'go to buy a OZ9910....

Update!
I've replace the OZ9910GN and something news appens. Now, while powering on, it flash for a brief moment, then goes black.
If I leave it powered on for some minute and try switch it off-on, sometimes it starts and works fine.
What can I check now?
Thanks
Carlo