Dell E2209Wc Display

[Tinkertodd]

Hello,

Long time reader, first time poster.

I've inherited a nice Dell E2209Wc that powers up but has a black screen. I can see the image on the screen when I shine a flashlight on it but not otherwise. I'm suspecting the power / inverter board.
I'd like to know if anyone has any advise about this monitor or has run into similar issues with it.

Thanks for reading!

[PlainBill]

Re: Dell E2209Wc Display

Hello,

Long time reader, first time poster.

I've inherited a nice Dell E2209Wc that powers up but has a black screen. I can see the image on the screen when I shine a flashlight on it but not otherwise. I'm suspecting the power / inverter board.
I'd like to know if anyone has any advise about this monitor or has run into similar issues with it.

Thanks for reading!

Have you opened the monitor up to see if anything is obviously wrong? If not, why haven't you?

If you opened the monitor up, did you take pictures of the power supply / inverter board? If you didn't why not?

If you DID take pictures, why didn't you attach them to your post?

Some of the people hare are very brilliant. Some of us are less so. Very few have memorized every problem and solution with every monitor they have ever repaired.

My advice: Follow the links in my signature. Open up the monitor. Take good pictures of the top and bottom of the power supply / inverter board. Attach them to your next post.

PlainBill

[Tinkertodd]

Re: Dell E2209Wc Display

PlainBill,

I have opened the monitor but nothing sticks out i.e the caps look okay to my novice eye.
I appreciate the advice and will take a picture and post that with questions.

Thanks for responding
Tinkertodd

[PlainBill]

Re: Dell E2209Wc Display

PlainBill,

I have opened the monitor but nothing sticks out i.e the caps look okay to my novice eye.
I appreciate the advice and will take a picture and post that with questions.

Thanks for responding
Tinkertodd

While deteriorating caps can cause a 'black screen' fault, the more common symptom is 'two seconds to black'. There often a fuse protecting the inverter circuitry. If it blows the result will be a totally dead inverter system. If you see one, Do NOT jumper it with a piece of wire 'just to see if that fixes it'.

PlainBill

[rooket_1000farads]

Re: Dell E2209Wc Display

While deteriorating caps can cause a 'black screen' fault, the more common symptom is 'two seconds to black'. There often a fuse protecting the inverter circuitry. If it blows the result will be a totally dead inverter system. If you see one, Do NOT jumper it with a piece of wire 'just to see if that fixes it'.

PlainBill

what does the inverter fuse look like? I saw on my 205bw circuit board "fuse" lettering but I didn't see any fuse nearby it. I replaced all the capacitors but was wondering what would happen if I ended up blowing the fuse one day, but I can't see it.

[Wrog]

Re: Dell E2209Wc Display

Inverter fuses are typically 1206 (3216 metric) surface mount package, like this. If you posted a picture of your inverter, it can probably be pointed out to you.

[Tinkertodd]

Re: Dell E2209Wc Display

Here are pictures of the board (as suggested, plainbill)
I tested the fuse (sircled in the fron picture) and power seems to be making its way through.
On the back of the board there seems to be a slight discoloration around one fo the IC's. Not sure if it wa just bad solderign or what but I did notice it after taking a long hard look. very slight discoloration, very slight.

All caps appear to be okay but I am new to al this.

Any help is greatly appreciated

[Wrog]

Re: Dell E2209Wc Display

What you have circled is the line fuse. If that were blown, you wouldn't get any power at all. Some boards have a smaller SMD fuse protecting the inverter side. Can you use macro mode on your digital camera for better pictures of the top/bottom?

[Tinkertodd]

Re: Dell E2209Wc Display

Wrog,

thanks for trying to help me.
I've tried to get some close ups of the board. Let me know whta you think.
Thanks

[Tinkertodd]

Re: Dell E2209Wc Display

OOOOOOOOOPPPPSSSSSS!
Here are the photos

[jetadm123]

Re: Dell E2209Wc Display

The supply generally puts out 5V (for the logic board and LCD display) and 12V (for the inverter circuit). Since you're getting a picture minus the light, we can say that the 5V is working. The 12V output is questionable. I'm guessing that the two heatsinked components to the upper left and right of the yellow transformer are the output diodes. They should be marked DXXX (where XXX is a 2-3 digit number). The middle lead on each should be the output. One diode should output 5V and the other 12V.

If you have verified the 12V, then do what wrog says and check for surface mount fuses marked FXXX. You will need to post a photo of the entire back side of the board. The photo you have is good, but we need the entire view of the board.

If a fuse checks bad, then one of the mosfet chips (Q802? or Q803) may be bad. You'll have to check them for shorts.

[Tinkertodd]

Re: Dell E2209Wc Display

Hi,
Yes they are diodes and there is a fuse surafce mounted next to one of them (see pic).
Do i need to have a "load" on the board to test it the way you are suggesting? That is to say do I have to have the board plugged into the lcd display and the logic board before I test for voltage or does it even matter?

I've also attahce a better pic of the back too.

Thanks for the help

[jetadm123]

Re: Dell E2209Wc Display

The full size photo is good, but the flash makes it almost impossible to read. Use some of PlainBill's suggestions in post #2 for good photos.

Check the resistance of the fuse first. It should be 0.3 ohms or less. If it's bad, then check Q802 and Q803 for shorts. What are the part numbers for Q802 and Q803?

If the things above check good, then you can check for voltage output. Some members will say you can check the power board without hooking it up, but I personally like to put everything back together before I test for the 5V and 12V outputs.

[PlainBill]

Re: Dell E2209Wc Display

Also, when someone says we need a picture of the entire back of the board, we need the ENTIRE back of the board. I've looked at all of the pictures you posted, and still can't spot where 12V is passed to the inverter.

PlainBill

[Tinkertodd]

Re: Dell E2209Wc Display

The numbers for Q802 are:
4828
BA9C15

Q803 is the same.

I've attached another picture, hope its better for you.

[Wrog]

Re: Dell E2209Wc Display

Hi,
Yes they are diodes and there is a fuse surafce mounted next to one of them (see pic).

That's not a fuse, it's something else (ferrite bead?).

Do i need to have a "load" on the board to test it the way you are suggesting? That is to say do I have to have the board plugged into the lcd display and the logic board before I test for voltage or does it even matter?

Typically, it's best to have everything hooked up the way it should be while taking measurements. Some power supplies require a load to start.

Take a look at the components I've circled. I can't see the reference designators but it looks like they could be the fuses we're looking for. Test it for continuity (open = blown). Also, it looks like someone has already done work to IC901... can you confirm?

[Tinkertodd]

Re: Dell E2209Wc Display

You're right it's not a fuse its a ferrite bead.

What you've circled are fuses (F902 & F801)

IC901: I doubt its been worked on since this was a new monitor my boss got that failed, then he gave it to me.
IC901 has allways been suspect since I started this project, something just didn't look right about it.

I'll test the fuses tomorrow and get back to you.

Thanks again

[jetadm123]

Re: Dell E2209Wc Display

Hi,
Yes they are diodes and there is a fuse surafce mounted next to one of them (see pic).
Do i need to have a "load" on the board to test it the way you are suggesting? That is to say do I have to have the board plugged into the lcd display and the logic board before I test for voltage or does it even matter?

I've also attahce a better pic of the back too.

Thanks for the help

I didn't look close enough at your first photo. Wrog is correct, that is not a fuse. It's not even surface mounted. If it's labeled FBXXX, then the FB stands for "Ferrite Bead". What Wrog has pointed out in the photo is what a surface mount fuse should look like.

[Wrog]

Re: Dell E2209Wc Display

After you've tested the fuses, I'd look at IC901 and surrounding pads/traces a little closer to make sure there's no solder bridging. Good luck!

[n3llyfl0w]

Re: Dell E2209Wc Display

I have the same problem that he has , i tun on my screen it shows up for 2 seconds then goes black and power light stays on ,i have no idea about power fuses and stuff like that , would it work if i bought the aoc power board new?