EEVblog Electronics Community Forum

Electronics => Repair => Topic started by: tpowell1830 on March 13, 2017, 06:57:58 am

Title: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: tpowell1830 on March 13, 2017, 06:57:58 am

I have 2 Acer AL2223W Monitors and one of them has stopped working. When the computer boots up I get an Acer logo screen and then the monitor shortly goes black. Also, if I unplug the VGA cable and plug back in, the screen shows my desktop for a second and then goes black. I haven't opened the back yet to see what I can see.

I was hoping to get some feedback if anyone has ever seen this before. I just want to get an idea where to start looking.

Any ideas are welcome.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: Cupcakus on March 13, 2017, 07:31:55 am

Check the electrolytic caps, that is almost always the culprit.  If they are bulging, they're easy to spot.  Just replace them all.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: netdudeuk on March 14, 2017, 01:52:55 am

Shine a torch really close to the screen. Do you see the image ?

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: james_s on March 14, 2017, 02:12:02 am

Is this LED or CCFL backlit? I've seen the same problem with a TV I fixed that had a bad LED in one of four series strings in the backlight. I've seen it happen with a CCFL that had a bad tube.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: tpowell1830 on March 14, 2017, 05:08:02 am

Thanks to all replies. I did the deed and opened the back and found a bunch of bulging caps on the power supply. I am in the process of replacing them now.

I will update when I get them in and tested.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: james_s on March 14, 2017, 06:39:52 am

Sounds like you're on the right track, I bet it will work fine once you replace those.

I remember when LCDs first came out everyone was moaning that they'd be impossible to repair. Surprise surprise, turns out they have one of the same problems that CRTs had. I've fixed dozens of them by replacing capacitors.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: Kim_555 on March 14, 2017, 07:03:43 am

After the power supply is malfunctioning, the processor may be damaged. Perhaps replacing capacitors to nothing lead. Since the condenser when dry - loses its parameters, and the voltage that it must filter - comes to monitor circuit.

Regards.

Title: Re: Repair Acer AL2223W Monitor - Comes on for a Second then Screen Goes Black
Post by: james_s on March 14, 2017, 03:51:48 pm

I've repaired dozens of LCD monitors and TVs by replacing capacitors. Usually when I get them they won't turn on at all though. Only a small number of them were not resolved when the capacitors were replaced.