Acer 2416B does not power on

[florabalance]

The history on this monitor is after a year or so of use it would intermittently display fine vertical lines instead of a normal display, eventually it would only display the vertical lines. Now it will not power on at all, the green led on the power button does not come on when you push the power button.

I have checked the standby voltage at pin 1 to gnd pin3 CNS1 on the power supply(to logic board) and it is 0v. Just for drill I also checked the fuse on the inverter board and they are all ok.

I am guessing this is a problem with the power board? I see no evidence of bulging capacitors on any of the boards including the power board.

Any guidance would be appreciated. Because the 1200px vertical monitors are uncommon these days I am hopeful I can get some more life from this one.

[addytzu123]

Re: Acer 2416B does not power on

Well, if the Led isn't powered at all, yes, the PSU is the first board to inspect. Before you go to inverter board, you should ckeck mains fuse on PSU and do a voltage testing, from input mains to output (voltage after mains fuse, voltage on the main primary filter capacitor, voltage on the PWM IC, and then output voltage).
Beside that, the lines on the screen may not be related entirely on PSU and suggest another issue, possibly on the pannel itself, according to your description.
Hi res pictures may bring you more targeted advices from other experienced users.

Adi

[florabalance]

Re: Acer 2416B does not power on

Before you go to inverter board, you should check mains fuse on PSU and do a voltage testing, from input mains to output (voltage after mains fuse, voltage on the main primary filter capacitor, voltage on the PWM IC, and then output voltage).

The fuse is ok(in the heatshrink I believe?), 115vac on in and out of the fuse, 165vdc across C1, I was not able to locate the PWM ic
My measurement of the standby voltage on pin 1 of cns1 was incorrect, it is in fact 5v, however pins 5-7 on that connector are all low, 4.59vdc to 4.63vdc

I have attached photos of the three boards, still have not led on the power switch, no power on.

[addytzu123]

Re: Acer 2416B does not power on

Hi,

If you do have voltages out, than most likely your primary side of PSU is fine.
Disconnect the inverter connector (just leave it open), the LED should have light without it.
Check the service manual attached (PSU are the same) and with a multimeter see if the voltages are in specs, on motherboard input connector.

It order to rule it out, see if the keyboard cable is well inserted at both ends, and that the powerswitch pushbutton is indeed working (put multimeter on buzzer/diode function, test leads on the pusbutton and press it).

But, first check the output voltages of PSU, with inverter board disconnected!

[florabalance]

Re: Acer 2416B does not power on

With the inverter board unplugged the 5v supply voltages going to the logic board came up to 4.87 - 4.89.

There was an apparent poor connection on the cable going to the keyboard, with the inverter reconnected now the power led comes on and I am back to the vertical lines, initially a white screen with a vertical grey bar, then the colored fine vertical lines begin to appear.

[addytzu123]

Re: Acer 2416B does not power on

So now the backlight is working?
4.89 V should be in specs, depending on your multimeter resolution.

Ok, now your problem could be located either on the Motherboard/LVDS cable or a faulty TCON board (TCON and Mainboard are joined by the LVDS cable, a thin ribbon type).
Very gently disconnect and reseat this cable at both ends, to see if it has any influence.
Usually a TCON boards have a small SMD fuse on them wich need to be checked as well.

Anyway, post some pictures, HI-Resolution, of mainboard and TCON !

Adi

[florabalance]

Re: Acer 2416B does not power on

yes, the backlight is working, thank you for the help with that.

I do not see how to disconnect the ribbon cable from the tcon board, the other ribbon connectors have a lock that swings open but I can't figure this one out, do you know? Also, did not locate a fuse on the tcon board?

I Posted the photos you requested.

[selldoor]

Re: Acer 2416B does not power on

Pictures are not really sharp enough for troubleshooting.
May be a white fuse at the top of the tcon near the connector but we really need to be able to read what it says on the board.

[florabalance]

Re: Acer 2416B does not power on

Here are better photos, was having problems with the lighting but think I have it resolved.

F5 would be the component to the left of the label with the J on it? It shows 0 ohms so would ok for a fuse.

[addytzu123]

Re: Acer 2416B does not power on

With everything connected normally and monitor switched on, what are the voltages on U18 and APL1084 3.3 (I can't see the part no from the picture).
Measure with multimeter set on 20V scale/or higher (if you have), black probe on the metal chasis and red probe on the middle pin (or the radiator they have on the back).

In the same way, with everything powered on, black probe on metal chasis and red probe after the SMD fuse on the TCON (where it is written "F5") and on U1, U2 and U3 from TCON (the same middle pin or the big copper plan undernith them).

Post the voltages!

[selldoor]

Re: Acer 2416B does not power on

Yes that is the fuse I meant
I am suspecting it may be a panel problem.
On the main board there is a resistor R17 - on your pic it is near the top connector.
It is 0 rated and as it does not look like a jumper may be acting as a fuse - test it the same
I cant see how that catch works may be the two white knurled bits at each side push in or that may just be somewhere to grip the cable? there is also that metal bit at one side does that move

Just a thought - you say you just have the lines on screen but have you got a source (PC) connected

[florabalance]

Re: Acer 2416B does not power on

r17 measures .2 ohm.

I was never able to get the other ribbon cable connector loose, I put it back together and hooked it up to my desktop, get the vertical lines-bar for a few seconds then it goes into standby(orange led-like no signal), the lines used to stay on all of the time.

If it is the panel then then it wouldn't be worth fixing I don't believe. I think the 5v supplies to the inverter board are low with it connected, 4.57 or so.

attached a photo of the bar/lines

[selldoor]

Re: Acer 2416B does not power on

Can you test the voltage regulators as Adi suggested.
Most helpers prefer you to test each of the 3 pins.

Fix the black lead on ground and test each pin with the red probe - the test and how to present the resuly is shown in retiredcaps guide
https://www.badcaps.net/forum/showthread.php?p=261329

Presumably if you could get rid of the gray lines you could live with the colored ones? Still need to find how to release that cable

[sabre504]

Re: Acer 2416B does not power on

These are usually a push fit .
Grip the 2 knurled lumps with finger and thumb and wiggle side to side a little and it should just slide out

[florabalance]

Re: Acer 2416B does not power on

I have tried several configurations with TCON but have not found an arrangement where I can have everything powered on and it connected, it is on the inside of the chassis next to the panel with 3 short ribbon cables.

Here are voltages of the 2 regulators on the logic/control board:

U18
APC 1117
AJ9 FR18
1 - 0v
2 - 1.78v
3 - 0v

33
APL1084
WJACL
1 - 0v
2 - 3.26v
3 - 0v

I would need to get rid of the colored lines also, they used to pretty much fill up the screen as time passed. Now, however it goes into standby in a minute or so.