Dell 2709w No power

[lalexan]

Re: Dell 2709w No power

Nice Thread... an it isn't dead, it's still alive.
Today I got three of these Monitors today for 0€, all marked defect.

Two of them starts normal, one shows the "blue power led stuck" error.

I think, I will start with this monitor and do the lalexan method:

And best wishes to all of you fine people

regards
Thomas

Hi Thomas, did it work for you?

A couple years after the fix the monitor failed again with the same problem. I needed to take the monitor through the same procedure again, and it works now. This time I heated it to ~230degC (sensed on top and 210degC at the backside of the board).

[Gold007]

Re: Dell 2709w No power

Hi guys!

I too have a 2709W with the following symptoms: Some (1-5 varying) vertical colour lines on each side of the screen that would go away after some time (10-25 minutes). The colour was a bit off too (rather warm, redish, purpleish).

I have reflowed the main chip using a sandwich maker and a hot air station with an IR thermometer. I have used lots of flux (even Louis Rossmann would approve) and could see flux squishing out from under the chip when touched with tweezers, so I am pretty sure the reflow was successful. I have also replaced most of the electrolytic caps around the two chips. Most of them were measurably degraded with pretty bad ESR readings.

After this, the screen works, the color is back to normal, but some lines are still present SoftMCCS still shows no DDC/CI (yes it is enabled in the monitor menu), so the chip is obviously not working correctly...
Maybe the chip is damaged permanently/internally? It does get warm but not crazy hot.

[Topcat]

Re: Dell 2709w No power

Hi guys!

I too have a 2709W with the following symptoms: Some (1-5 varying) vertical colour lines on each side of the screen that would go away after some time (10-25 minutes).

This is a defect in the panel's tab bonds, there is no fix for it. Well known issue for this monitor.

[Gold007]

Re: Dell 2709w No power

This is a defect in the panel's tab bonds, there is no fix for it. Well known issue for this monitor.

Thank you for your reply! This is sad to hear, but then I guess there is nothing to do about that...
This explains the lines on the screen, but DDC/CI not working seems a bit suspicious for me. I doubt it has anything to do with tab bonds making contact or not. But then who knows. I think I will just live with the lines and I don't use DDC/CI anyway At least now I know the electrolytics are good and the BGA should be fine for a few years at least.

[k4wers]

Re: Dell 2709w No power

hi. i have this monitor, i've replaced some caps but something happened to the schematic and its ruined, now i dont know where the caps go, cant find a schematic, ¿can anyone send me a picture showing what values are the caps from the main board please? thanks.

[Bob789]

Hello all 2709W friends - or "2709W victims"??

Yes, an old thread, but still active (Oct 2023) - and very informative, thank you all!

My 2709W worked well for more than 12 years (very good, I still like it!!), but had troubles recently, to the point of a "no image" failure. Being a rather occasional DIY electronics repair person, I read this thread and others and started disassembling the 2709W, removed dust and tested a few things.

-> Unfortunately I must have caused a short somewhere because suddenly smoke was rising and the component Q603 on the main board (a MOSFET?) was dead, see picture below.

A web search for "A1PV", half leggible on the damaged Q603, unfortunately did not come up with any relevant information.

Questions:

• Does anyone know which component (exactly) Q603 is?
  I guess it's a transistor or voltage regulator. The "D" in the corner (red arrow) could mean "drain". Dimensions are 2.9 x 1.6 mm (SOT23 or SOT23-3).
• Which voltage should I get at the solder point to which the yellow arrow points in the picture below (on a healthy board)?
• Resistor R661 (marked "104" -> 100 kOhm) seems to have gotten some heat too. Better to replace it as well?

Thank you very much for any help!!

[lotas]

A1xx - AO3401 (30V P-Channel MOSFET).

[Bob789]

Wow!! Thank you very much!! So fast!

Have a nice evening!

[tony359]

Hi there,

My dell 2709 died some weeks ago and this is one of the most informative threads I found online on the subject. I managed to fix it and made a video repair, I mentioned this forum and linked this thread in the description.
I've had three DELL's monitor of that era which ALL failed for the same reason. I wonder whether whoever re-flowed the main processor actually unintentionally "fixed" the same issues all my monitors had!

Feedback always very welcome

[k4wers]

En Castellano:

Hola, tengo el monitor 2709WFPb. Cambié los condensadores, dañé la placa y conseguí una nueva. La conecté, pero no se encendió. Hoy fui a la tienda de un ingeniero electrónico de la ciudad, y me dijo que podía revisar la fuente de alimentación con su osciloscopio. Hice algunas pruebas y había voltajes correctos en algunos puntos... alrededor de 18V, pero él comentó que necesitaba verificarse con el osciloscopio.

Cuando le llevé el panel con las placas, me dijo: “Ah, es un LCD, no un LED... déjalo, hijo. Estas cosas tienen tubos que se desgastan con el tiempo, y hay un circuito que lo detecta y hace que el monitor no se encienda o se apague automáticamente... Y, tal vez, podrías cambiar uno de los tubos, pero se rompería en unos 3 meses. No malgastes tu dinero”.

Así que… QUIERO CONVERTIR ESTE LCD EN UN LED.
¿QUIÉN SE APUNTA A ESTA AVENTURA?
Y lo más importante de todo: ¿cómo podemos engañar al sensor que detecta el fallo de los tubos del LCD?

---

In English:

Hi, I have the 2709WFPb monitor. I replaced the capacitors, damaged the board, and got a new one. I plugged it in, but it didn't light up. Today, I went to an electronic engineer's shop in town, and he said he could check the power supply with his oscilloscope. I tested it, and there were correct voltages in some spots... around 18V, but he said it needed to be checked with an oscilloscope.

When I showed him the panel with the boards, he said: "Oh, it's an LCD, not a LED... give up, son. These things have tubes that wear out over time, and there's a circuit that detects this, causing the monitor not to light up or shut down automatically... And maybe you could replace a tube, but it would break in about 3 months. Don't waste your money."

Now... I WANT TO TURN THIS LCD INTO A LED.
WHO WANTS TO JOIN THIS ADVENTURE?
And most importantly: how can we bypass this LCD tube sensor censorship?