Dell 1800fp

[junktv]

Re: Dell 1800fp

Update

I finally got back around to this monitor. I replaced 2 caps with 33uf 25v and 47uf 50v and it works so far. I did get a flicker for about 1-3 seconds the first time i turned it on and again after i unplugged it and let it sit. It doesn't seem to flicker if i leave it plugged in.

[jetadm123]

Re: Dell 1800fp

Update

I finally got back around to this monitor. I replaced 2 caps with 33uf 25v and 47uf 50v and it works so far. I did get a flicker for about 1-3 seconds the first time i turned it on and again after i unplugged it and let it sit. It doesn't seem to flicker if i leave it plugged in.

A common problem with this model monitor are bad solder joints on the main transformer and duo diode packs. You might consider resoldering these joints.

[junktv]

Re: Dell 1800fp

Well it flickers on start up even if plugged in. I guess i didn't let it sit long enough.

I'm 95% sure I did go back over all those because i have a 15" dell that had issues with solder joints.

One thing i noticed today is a really quiet buzz. With a stethoscope i tracked it down to these coils. Sorry i'm not sure what they are called.

[MBLeo]

Re: Dell 1800fp

IC901 ICE2AS01 burns out because the solder on T901 and on D903 and D906 is bad...I have found the repair kits with directions on eBay for very little money and the two I repaired work fine...

[junktv]

Re: Dell 1800fp

Uh oh. Been using this again and turned it off the other day and now when you turn it on the flashing doesn't stop.

Time to open it up again.

[junktv]

Re: Dell 1800fp

Well re-resoldered again and no luck. Everything works just constantly flickers. No obvious bad caps or bad joints. Haven't tried a hair dryer yet

[Relayer]

Re: Dell 1800fp

Hello junktv,
When you say it flickers, do you mean you get a black screen, or does it flare white?
Regards,
Relayer

[budm]

Re: Dell 1800fp

The DCV output is steady or not?
https://www.badcaps.net/forum/attach...7&d=1338497270
You should check or replace those two startup/running caps next to the SMPS IC.
The rectifier in the cold side is OK?

[junktv]

Re: Dell 1800fp

Hello junktv,
When you say it flickers, do you mean you get a black screen, or does it flare white?
Regards,
Relayer

Full image 100% of the time but the back light flickers. It's done it since last "fix" but stops after a few seconds then.

Have a newer led hanns g that page code will shut it down if you know why but that is another topic.

[junktv]

Re: Dell 1800fp

The DCV output is steady or not?
https://www.badcaps.net/forum/attach...7&d=1338497270
You should check or replace those two startup/running caps next to the SMPS IC.
The rectifier in the cold side is OK?

I've not tested it. Just striped and looked de and re soldered. The little ones i replaced with panasonic? Next to the ic that is china only now. May have put a ucc on the lower right of the pic.

[Relayer]

Re: Dell 1800fp

Hello junktv,
Could you please check any high value resistors around or near IC901?
You need to lift one leg to obtain an accurate reading. High value will mean anything at or above 100kΩ.
Please see picture below:



As shown in the green shaded area is where you need to look for any high value resistors.
Also, the boxes shown on your power out connector, I assume that the twin pins are physically tied together? The 4 ground pins as well?


Please see next picture:



It would be good if you could obtain a couple of automotive incandescent light globes to use as a dummy load on the PSU to determine if the 12 volt rail remains steady. You may need to leave it like that for a while to see if there is any fluctuation. Therefore you'll need your multi-meter to be connected during the test.
Both globes can be 12V types, but make sure they can at least handle 30 Watts or more, but not too much more. Say 30W to 50W would be fine.
One more thing, polarity on the globes doesn't matter, but make sure that when you attach the wires to the PSU that you connect them on the solder side and not to the connector pins on the component side.

By the way, I assume you've already replaced the capacitor as indicated by the green arrow?

Please let us know how you get on.
Regards,
Relayer