Re: ACER AL2423W - no display



On the PCB, it shows three voltages and currents:
5V@3.5A
12V@2.0A
19V@3.5A

Interestingly, there are two traces that connect the logic board to the inverter board. The PCB is the exact same as [URL="https://www.badcaps.net/forum/showthread.php?t=9773"]here[/URL] (multiple posts and pictures). I plan to take it apart for probing purposes but all the Metcal stuff is at work. Not that I am working on SMT parts, but they have better heat dissipation than most end-user soldering irons. Thanks...

Re: ACER AL2423W - no display



Thanks, I just didn't know if the logic board is supposed to 'enable' the 12V section. I.e., is the 12V not being enabled, or should it power up immediately, or does the logic board, having not seen 12V, immediately shuts down (5V still present).

I see that there is a 19V section, I wonder if that is used for boost converter section for the backlight....

Re: Acer AL2423W: Recapped, Still Dead!



CleanSC: I have just the opposite problem, 5V present but no 12V. I saw in one of the posts here that it was proposed that the 5V rail is first to have power, then the logic board turns the 12V rail on. Is that right? I have no 12V rail, and when I power on the monitor, the green LED quickly goes out (~50-100ms).

I also accidentally posted in the [URL="https://www.badcaps.net/forum/showpost.php?p=135743&postcount=70"]wrong thread [/URL] asking you for a blowup of the speaker wires (broke off at the...

Re: ACER AL2423W - no display



Thanks, looks like 12V rail is dead. 5V is present (but only used for logic). I assume the 12V is used for the DC/DC fluorescent back-lighting. Can the PSU be operated safely without any load on 5V or 12V? Some PSUs are unstable in this mode, I just don't know if this is one of them! ...

Re: ACER AL2423W - no display

CleanSC: I accidentally ripped the wires out of the 1x4 header for the speaker output. Could you kindly zoom in on one of your pictures around the connector? Thanks!

My monitor just died recently (same model). ACER repaired it in January 2010, and they said they replaced the Power Supply. Now it is out-of-warranty. No bulging caps. Symptoms are that when I turn the power switch on, the green LED power light goes on and out quickly. It could be some kind of power supply watchdog to ensure all rails are present (and power off if not), or...