Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

So, I'm a little bit embarrassed to even post these photos, so you'll just have to realize that I suck at soldering.

I got the caps in the mail today and began the repair job. The one that had the pad ripped off was much more difficult because the solder wouldn't stick down. While I was trying to get it, the soldering iron touched some of the metal channels next to it (in the pictures you can see what a mess it made). Can anyone tell me the purpose of those metal channels? I assumed that they are not all separate, electrically, because you can see the channel underneath surrounding several of them.

Anyway, I got the soldering done on that cap and the other caps, and put the board back in. The monitor turned on fine! Then I put some of the back panels back on and tried it again. This time, it had the same problem as before. Buzzing, then sizzling out to nothing. I was worried that it was another part, but after inspecting everything again and not finding anything, I decided I may have knocked the cap loose and so I resoldered it. This time, it worked again, and stayed working.

You can see that I left solder across 2 of the channels, but it looks like they are part of the same electrical circuit. Does anyone think this will be a problem?

I got the monitor assembled back together and everything seems to be working great. $5 in parts and it's back to life! Thanks to everyone for the advice, especially retiredcaps, there is no way I could have got it working without this forum.

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

So just to be clear, the pad is actually gone but just soldering the new capacitor on there should (hopefully) work without doing anything special?

Yes.

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I feel a need to find whoever designed this board and .... you fill in the blank!!

Yeah they designed it like some kind of puzzle you'd find at the Sharper Image...

[Dgtech]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I feel a need to find whoever designed this board and .... you fill in the blank!!

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

From the pic, it looks like you just lifted the pad and it is gone. The traces are underneath the green and you would have to sand it off to expose them.

So just to be clear, the pad is actually gone but just soldering the new capacitor on there should (hopefully) work without doing anything special?

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

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Except, I'm not sure exactly how to identify pads and traces.

From the pic, it looks like you just lifted the pad and it is gone. The traces are underneath the green and you would have to sand it off to expose them.

Don't worry too much. I have lifted a few solder pads when I first started soldering and managed to get them working.

I may not have had enough heat. My soldering iron is, I believe, the 15w Radio Shack special (believe it or not actually recommended for xbox mod chips because of the lower heat).

I'm not a solder iron expert, but I believe 15W is fine IF your tip is clean and somewhat large. 15W may be insufficient for RoHS lead free boards though?

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I don't have the skills to fix a burnt off solder pad, but I have read somewhere about attaching new ones, but it is a lot of work. Search for "install new solder pad".

Having said that, I think you should be okay installing the new cap. Just get enough solder on that bottom hole to hold it in place.

I found this quote on desoldering:

Occasionally, you may damage a solder pad in your efforts. Usually, this just involves lifting the pad from the board, but not actually separating the traces. If this is the case, then it should be fine if you just leave it. If this is not the case and you actually break the trace, you will need to use a small piece of wire to connect the pad to where it is supposed to go. Just follow the trace until you find a suitable location for soldering. Usually, this is the next closest solder joint. Then, jumper the wire between the two points.

Except, I'm not sure exactly how to identify pads and traces. I couldn't identify anything directly connected to the solder joint for the cap I removed.

My soldering iron is your typical 40W ebay sort by lowest price special. One day, I might get a Weller or Hakko.

I may not have had enough heat. My soldering iron is, I believe, the 15w Radio Shack special (believe it or not actually recommended for xbox mod chips because of the lower heat).

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

What can I do to fix it if it's "burnt off" or broken off as you say? I don't know much about circuit connections.

I could replace them but I'm worried about the resulting amateur soldering being a greater liability than a poorly made original capacitor.

I don't have the skills to fix a burnt off solder pad, but I have read somewhere about attaching new ones, but it is a lot of work. Search for "install new solder pad".

Having said that, I think you should be okay installing the new cap. Just get enough solder on that bottom hole to hold it in place.

The key to desoldering, I find, is to add a little bit of 60/40 rosin core solder. I add just enough to cover whatever I'm desoldering. Then I use my desolder pump and suck it up. It leaves the solder pad in place and all the solder is easily removed.

If you have some junk boards, you can practice the above.

My soldering iron is your typical 40W ebay sort by lowest price special. One day, I might get a Weller or Hakko.

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

You might want to reflow or resolder the transistors attached to that heat skink after you have bent the heat sink back in place. Moving the heat sink around may have cause the solder on the transistors pins to move around?

Also, you may have used a bit too much heat on the bottom hole pad. The pad seems burnt off? I usually add a little bit of solder to whatever I'm desoldering first. It makes the old solder melt better without using a lot of heat.

Good job on the jailbreak cap! :-)

edit: BTW, you have clear access to at least 3 other caps. You may want to think about replacing those as well. I know I said to replace just the bulging one, but I didn't know beforehand that the jailbreak would expose access to the other ones.

Well the story on the big cap is - I don't have a great soldering iron and I ended up with a mix of heating it, and having to wiggle it loose and then chip off the solder. I may have broken off whatever was there before... What can I do to fix it if it's "burnt off" or broken off as you say? I don't know much about circuit connections.

There are a total of 6 more caps under there, of what looks like 4 different types. I could replace them but I'm worried about the resulting amateur soldering being a greater liability than a poorly made original capacitor.

[Edit] I'll also do as you suggest with the transistors once I've got the heat sink bent back down and putting it all back together.

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I am worried I may have cracked something loose while doing so, but I can't see any damage.

I've also attached pics of the boards after removal, so if any of you experts see any damage or problems please let me know

You might want to reflow or resolder the transistors attached to that heat skink after you have bent the heat sink back in place. Moving the heat sink around may have cause the solder on the transistors pins to move around?

Also, you may have used a bit too much heat on the bottom hole pad. The pad seems burnt off? I usually add a little bit of solder to whatever I'm desoldering first. It makes the old solder melt better without using a lot of heat.

Good job on the jailbreak cap! :-)

edit: BTW, you have clear access to at least 3 other caps. You may want to think about replacing those as well. I know I said to replace just the bulging one, but I didn't know beforehand that the jailbreak would expose access to the other ones.

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I don't have anyone better at soldering to help me with this so I took retiredcaps suggestion and bent the heat sink. I am worried I may have cracked something loose while doing so, but I can't see any damage. I got the cap out and took out the caps on the other board. I followed PlainBill's advice (thank you!) on the other thread for ordering from DigiKey and have the following in my basket.

http://search.digikey.com/scripts/Dk...name=P10230-ND (1)

http://search.digikey.com/scripts/Dk...name=P10294-ND (2)

I measured the size and these two match pretty well, if not exactly. Thanks everyone for your help, I'm going to double check the parts and then make the order!

I've also attached pics of the boards after removal, so if any of you experts see any damage or problems please let me know

[PlainBill]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Wow, that design with the heat sink covering those caps (and the devices screwed to both sides) really sucks.

Yeah, they cover two birds with one stone. The design makes for an early failure, particularly with low quality caps. And it makes it almost impossible to repair. You have to remove the solder from the component legs (difficult) and from the heat sink (really tough).

PlainBill

[smason]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Wow, that design with the heat sink covering those caps (and the devices screwed to both sides) really sucks.

[shovenose]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

replace those 2 small ones too- defintiely

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Sorry, I thought it was suggested in the image posting tutorial you linked to? (for referring to specific pictures)

Inline is optional, but not preferred. It slows down the loading of a page while huge images are loaded.

At least they will be easier to replace. Can you tell me what "bad" might mean in this case, assuming this damage was not recent (and the monitor was working fine before)?

Bad meaning that these 2 capacitors are malfunctioning which makes the other components work harder. When they work harder they are bound to fail.

Think of it this way. You have a brake on each wheel of the car. Now imagine 2 of them not working properly (bad). Your car will still stop, but the other 2 have to work so much harder. Not to mention the other extra unneeded stress on your joints, structure, etc. With this extra stress, these components will fail sooner than necessary.

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

BTW, please don't put inline pictures into the text. We can click on what we want to see in a bigger image.

Sorry, I thought it was suggested in the image posting tutorial you linked to? (for referring to specific pictures)

Yes, those are bloated and bad too. They are Capxon KF series made in 2007 week 11 (C711 code).

At least they will be easier to replace. Can you tell me what "bad" might mean in this case, assuming this damage was not recent (and the monitor was working fine before)?

Thanks again for your quick responses.

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

I'm pretty sure removing all of those transistors and correctly reinstalling them would be beyond my ability.

Do you have any friends good at electronics and soldering? If yes, offer a 6 pack in exchange for soldering.

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Alright, I have some new pictures and I'd like to know how screwed I am.

BTW, please don't put inline pictures into the text. We can click on what we want to see in a bigger image.

First of all, I took a closer look at the heat sink, and it looks like there is no way to completely detach it from the transistors before removing the transistors from the board, since one of the screws goes all the way through two of them and is butted up right next to a cap under the heat sink.

Hmm, if no one else has ideas, I guess you can try and bend/pry just enough of the heat sink back to replace one bad cap and leave the others alone?

Secondly, I'm worried about the cap on this other board, it looks like it's slightly bulging (but I haven't had problems with this monitor prior to this power problem).

Yes, those are bloated and bad too. They are Capxon KF series made in 2007 week 11 (C711 code).

[Renesis13]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Alright, I have some new pictures and I'd like to know how screwed I am.

First of all, I took a closer look at the heat sink, and it looks like there is no way to completely detach it from the transistors before removing the transistors from the board, since one of the screws goes all the way through two of them and is butted up right next to a cap under the heat sink.

.

I'm pretty sure removing all of those transistors and correctly reinstalling them would be beyond my ability.

Secondly, I'm worried about the cap on this other board, it looks like it's slightly bulging (but I haven't had problems with this monitor prior to this power problem).

[retiredcaps]

Re: Westinghouse L2410NM 24" LCD power goes on and off, blue light flickers

Will I need to do anything special (like on a processor) for reinstalling the heat sink?

Possibly. The transistors may need some artic silver or similar type of compound. I believe in this video Maxxarcade (who is a member here)

http://www.youtube.com/user/Maxxarca.../2/SoL1k8Jk_Z8

talks about a special compound for mounting audio transistors.

markm75 - Sorry for my ignorance, but what is the inverter board? I did a google search but couldn't figure out what in my specific monitor the inverter board is (but I'm guessing it is the tall boar on the right?)

Yes, it is the tall board.