LCD colour distorted after capacitor change

[yodude010]

Hello guys!!

I need some help.

I've HP 1702 17" LCD Screen. Few days back it started flickering on startup. So I decided to change the capacitors. After opening the lcd panel, i found that one capacitor(1000uf 16v) had become fat and the other one(470uf 16v) had popped. I decided to put 1000uf 25 and 470uf 25v. After capacitor change, my lcd became reddish. I've attached some photos.

I thought it might be due to voltage increment, therefore I decided to put 1000uf 16v and 470uf 16v but the result is the same.

The capacitors were located near power supply(on yellowish type board).

Could you please give an idea on what's wrong? the flickering thing has gone, but lcd colours are like you don't have vga drivers installed.

Thanks

[kc8adu]

Re: LCD colour distorted after capacitor change

reseat the lvds cable.goes to the panel.

[yodude010]

Re: LCD colour distorted after capacitor change

I've double checked. All the connecters are fitted properly. I tried to change the lcd ribbon direction by fitting it upside down, but it doesn't work. I'm unable to locate the problem. All others caps are looking fine to me.

[mockingbird]

Re: LCD colour distorted after capacitor change

No, voltage increase is a GOOD thing, because it's only a rating and will extend the life of the recap. Always use more voltage where you can fit it in.

Things you need to do:
1) Change ALL the capacitors (Except for the main primary)
2) List the series of the capacitors. You can't just replace capacitors with anything of the same value. It has to be the same series.

[yodude010]

Re: LCD colour distorted after capacitor change

^ Thanks dear. I'v to travel out of city for a few days. I will try to do it after coming back. I will also post the lcd board images so that you can suggest me which ones to change.

[Th3_uN1Qu3]

Re: LCD colour distorted after capacitor change

I've double checked. All the connecters are fitted properly.

Then clean them with a cotton swab wet in isopropyl alcohol and try again. That reddish tint is a typical symptom of a improperly seated/dirty cable.

[Badcappy]

Re: LCD colour distorted after capacitor change

Is it the panel that's turned red or the backlight? If it's the latter, you might be due for a CCFL replacement.

[Th3_uN1Qu3]

Re: LCD colour distorted after capacitor change

It's the panel, i've seen that issue before when i put my PDA back together with sweaty hands. Once i cleaned the cable and reseated it, the reddish tint went away.

[kc8adu]

Re: LCD colour distorted after capacitor change

maybe you damaged the cable when you pulled it apart the first time?
had 2 visio lcd tv's with that issue.one red one green.bad crimps in the panel end of the lvds.easy fix.

[yodude010]

Re: LCD colour distorted after capacitor change

Hello guys, sorry i was away.

I checked the cables. All cables are fine. I'm attaching some photos of the board.







@badcappy

When the pc is disconnected, while showing "monitor is going to turn off" the back screen is also reddish. Does that mean the backlight is dead?

[yodude010]

Re: LCD colour distorted after capacitor change

any help?

[Agent24]

Re: LCD colour distorted after capacitor change

I tried to change the lcd ribbon direction by fitting it upside down, but it doesn't work.

I'm not 100% sure what you mean by this, but cables go in the way they are supposed to go in for a reason.

Putting cables in backwards is a good way to cause even more problems.


I can't help you much either, but I do have a monitor with faulty CCFLs and the whole screen is very red, it makes a bad hissing noise and then shuts down.

If that doesn't happen to you then your CCFLs are probably fine.


Oh and please don't post your photos in-line in your posts (unless you resize them).
Just attaching them is OK.
Not everyone has a 50" widescreen monitor...

[Pyr0Beast]

Re: LCD colour distorted after capacitor change

Let LCD warm up and see if reddish tint dissapears. Old cold cathode tubes often turn a bit pink but work well anyway.

[tonyny]

Re: LCD colour distorted after capacitor change

hello, I'm new but I seem in another site that your problem is the backlight I don't know if I can post a site name were you can get that information and buy the parts

[l3igl3ang]

Re: LCD colour distorted after capacitor change

Hi guys my 42" sanyo lcd is doing the same thing and i checked all the cables and cleaned them. How did u guys ever fix the problem?

[swgaspidey]

Re: LCD colour distorted after capacitor change

bad ccfl backlights can also cause a color change