Taking apart a gv42l and troubleshooting

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

if you are referring to me. I must apologize. I am also new to posting on websites, forums and blogs. Please accept my apologies. I am only reaching out for a bit of help and, found this site by trying to research the problem I am having.

You also refer to "Unpaid" members. IF I can find exactly where to pay or donate I will have NO problem paying or donating to such a useful site which can possibly help me to repair some of the many LCD televisions which I decided to keep and repair.

I apologize if I seem stupid or, ask stupid questions or " cross reference" I am not only learning how to diagnose and repair LCD televisions but, also, learning how to properly respond and ask questions. IF I am asking in the wrong area or, duplicate please feel free to tell me. Every one has a 1st day on the job right?

Thank you again and, I will appreciate any help with this set before I decide to simply send it to the shredder where most boards here go.

Thank you again

John

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Does anyone have a schematic for this board? I think I can try to read the schematic to determine what voltages are supposed to be present.
I am really not too sure how to read it but, I can surely try

[Silviyius]

Re: Taking apart a gv42l and troubleshooting

look up your part number on the chip and look it up on digikey. The tv on this thread has a different board which doesn't include a u33 regulator. Also The rules are a good thing to read before making a post. I hope you find your part. Also would help if you told us which board you have.

Hijacking is one of them...

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Hijacking? what is hijacking? It might be a good idea to let new people know how to research properly. rather than scolding them for making an honest mistake. I am human after all. maybe I should be shot at the stake or hung for such an injustice. i am sorry and, I said I am sorry MANY times. but, again, I am NOT a computer person at all, I am actually a retired US Air Force Veteran trying to find a hobby and, NOT very experienced as yourself regarding how to ask questions, how to ask for help, on the computer or on blogs, message boards, etc. I just thought that this site was a friendly and helpful site for regular people. I had NO idea that it was a requirement to know the rules of computers and, how to ask properly. otherwise, I surely would have. So. again, please accept my apologies Otherwise, i will simply throw this non-working television into the dumpster and forget aboit it. I simply cannot beg anymore

I am simply asking for a little help with something which I cannot understand or, actually read the #'s on a chip which I have read, on this site, that is the culprit or problem preventing this television from working.

Please do let me know if I am asking too much and, I will simply just go away

thank you

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Also, I have finally found the U33 part which is referred on this blog or message or, whatever it is called but, have NO idea how to find a replacement

Please let me know where the site which refers to the U33 is located and, how to find a replacement somewhere?

As a matter of fact, I will simply add this television to the pile at the local landfill since, it obviously appears that I have committed some some terrible crime and, not welcome to help here.

does not seem too fair but, I must abide by the rules which I do not quite understand.


Thank you very much for the info which this site has provided me so far

Jon

I will not be bothering you any further with my problems simply because, I am not familiar with the rules for asking a question

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Hijacking? what is hijacking? It might be a good idea to let new people know how to research properly. rather than scolding them for making an honest mistake. I am human after all. maybe I should be shot at the stake or hung for such an injustice. i am sorry and, I said I am sorry MANY times. but, again, I am NOT a computer person at all, I am actually a retired US Air Force Veteran trying to find a hobby and, NOT very experienced as yourself regarding how to ask questions, how to ask for help, on the computer or on blogs, message boards, etc. I just thought that this site was a friendly and helpful site for regular people. I had NO idea that it was a requirement to know the rules of computers and, how to ask properly. otherwise, I surely would have. So. again, please accept my apologies Otherwise, i will simply throw this non-working television into the dumpster and forget aboit it. I simply cannot beg anymore

I am simply asking for a little help with something which I cannot understand or, actually read the #'s on a chip which I have read, on this site, that is the culprit or problem preventing this television from working.

Please do let me know if I am asking too much and, I will simply just go away

thank you

look up your part number on the chip and look it up on digikey. The tv on this thread has a different board which doesn't include a u33 regulator. Also The rules are a good thing to read before making a post. I hope you find your part. Also would help if you told us which board you have.

Hijacking is one of them...

????????????????????

as though you know???????????/

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Thanks all for the kind help

[retiredcaps]

Re: Taking apart a gv42l and troubleshooting

Also, I have finally found the U33 part which is referred on this blog or message or, whatever it is called but, have NO idea how to find a replacement

Please let me know where the site which refers to the U33 is located and, how to find a replacement somewhere?

The answers to all your questions with detailed instructions on how to test and the correct part numbers with where to order are in the original thread that you started. You have to read through it all.

https://www.badcaps.net/forum/showthread.php?t=13792

The reason I asked you not to cross post (post in more than one thread) is exactly for this reason. The TV discussed here doesn't even have a U33 (post 9, 10, and 11 make that clear) so you don't have the same board. Asking questions about your board confuses the regulars here because the two boards are not the same and we have to keep track of who is asking what.

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

1st, I do not did have a camera to take pictures, I surely would NOT have any idea how to upload the pictures.

I am simply asking whether ANYONE knows what the # is I SIMPLY cannot ! see the #'s on the chip SO, I can try to cross reference the needed part and buy it from digikey or wherever

It seems that this is much harder to ask than finding the part. Is it some secret?

Where do I pay to receive some help? I have NO problem with paying at all

Just so i will know where to collect on the 100's of tips and "secrets" on how I personally repaired other televisions.and, I am 100% certain that I will receive $1,000's for the info I have acquired over the years

Jon

[selldoor]

Re: Taking apart a gv42l and troubleshooting

Hi electronicsurplus, I have been reading this thread and have responded on your other one.
https://www.badcaps.net/forum/showpo...0&postcount=44
It would help us if you did not continue on this thread.

[Silviyius]

Re: Taking apart a gv42l and troubleshooting

The suffix in the part number denotes the correct output voltage. For example, -18 denotes 1.8V should be the correct voltage. Most voltage regulators are +/- 1%.

Since every regulator "after" U5 is way way off, U5 would be a good starting point. Since there is no suffix in U5's part number, that is an adjustable voltage regulator.

Budm explains how it works here ...

https://www.badcaps.net/forum/showpo...4&postcount=65

Originally Posted by Silviyius View Post
u5 pin 1: 0.23v pin 2: 0.64v pin 3: 3.33v part #: amc 1117 F0629J
u7 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L
u8 pin 1: 0v pin 2: 1.34v pin 3: 0.84v part #: ac 6G9L 17-33L
u9 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L
u10 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L
u16 pin 1: 0v pin 2: 0.11v pin 3: 0.84v part #: ac 6F2L 17-25L
DU2 pin 1: 0v pin 2: 1.15v pin 3: 0.70v part #: ac 6G9L 17-33L
DU3 pin 1: 0v pin 2: 0.03v pin 3: 0.69v part #: ac 6F2L 17-25L
DU4 pin 1: 0v pin 2: 0.90v pin 3: 1.94v part #: amc 1117 F0629J

I'm a little confused about the ouput formula. and can someone educate me on why we dont sell the parts by the model number? it seems the amc for example can only be found by 1117. how to get the true model number is beyond me...

[electronicsurplus]

Re: Taking apart a gv42l and troubleshooting

Thanks everyone, replaced U33 and wala it workedeven though I used an electrically equivalent but much larger size, i soldered it standing up and glued it in place works like a charm

Thanks again gentlemen

another set saved from poisoning our landfill

[budm]

Re: Taking apart a gv42l and troubleshooting

"u5 pin 1: 0.23v pin 2: 0.64v pin 3: 3.33v part #: amc 1117 F0629J"
U5 is definitely bad, this an adjustable 1117 series regulator, the voltage between pin 1 and pin 2 should be 1.25V, right now it is only about 0.41 volt. I would replace this one first.
All other all read wrong also:
u7 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L (1.8V Fixed regulator)
u8 pin 1: 0v pin 2: 1.34v pin 3: 0.84v part #: ac 6G9L 17-33L (3.3V Fixed regulator)
u9 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L (1.8V Fixed regulator)
u10 pin 1: 0v pin 2: 0.51v pin 3: 1.34v part #: ac 6F5L 17-18L (1.8V Fixed regulator)
u16 pin 1: 0v pin 2: 0.11v pin 3: 0.84v part #: ac 6F2L 17-25L (2.5V Fixed regulator)
DU2 pin 1: 0v pin 2: 1.15v pin 3: 0.70v part #: ac 6G9L 17-33L (3.3V Fixed regulator)
DU3 pin 1: 0v pin 2: 0.03v pin 3: 0.69v part #: ac 6F2L 17-25L (2.5V Fixed regulator)
DU4 pin 1: 0v pin 2: 0.90v pin 3: 1.94v part #: amc 1117 F0629J (Adjustable regulator)

The above voltage reading on the input pin (pin3) are ALL too low for the regulator to work, so we need to find out why after you replace U5.

[Silviyius]

Re: Taking apart a gv42l and troubleshooting

thanks budm. Lastly is there a easy way to track down these parts?

[selldoor]

Re: Taking apart a gv42l and troubleshooting

Hi - here is another Budm explanation here which has a few more examples
https://www.badcaps.net/forum/showpo...2&postcount=80.
Part numbers - no answer a lot of guesswork intuition and research often required.
The part number IS 1117 on that particular chip AMC is the manufacturer a common replacement is LM1117 where LM is the manufacturer. Fairchild also produce one FAN1117
and so on. I think there is a list of manufacturer prefixes somewhere but cant just spot it. As stated your test results dont look good.

Ebay or digikey is your best bet

[budm]

Re: Taking apart a gv42l and troubleshooting

If they are the small body TO223, then Digikey will be the place to get them from.
See examples.

[kc8adu]

Re: Taking apart a gv42l and troubleshooting

great!got your first win.
several things to note in the future.get a decent camera and learn to use it.
in these type of threads a picture is worth MORE than a thousand words.
researc via search your brand and model.i still dont know what set you have.
enter an ongoing thread with your observations and maybe questions IF the problem is related.
otherwise start another.we dont want the confusion of working 2 unrelated issues.
so welcome and hope you fix many more devices.

Thanks everyone, replaced U33 and wala it workedeven though I used an electrically equivalent but much larger size, i soldered it standing up and glued it in place works like a charm

Thanks again gentlemen

another set saved from poisoning our landfill

[Silviyius]

Re: Taking apart a gv42l and troubleshooting

Sorry for such a late post. I finnaly got the tv working. It was u5 that needed to be replaced. Once i did i got a picture again. I did however... I broke the led and ir cable. dose anyone know where i can replace these cables? if they have a generic name or something I've looked everywhere.

[retiredcaps]

Re: Taking apart a gv42l and troubleshooting

I broke the led and ir cable.

Post a picture of the damage. It may be repairable?

[retiredcaps]

Re: Taking apart a gv42l and troubleshooting

I finnaly got the tv working. It was u5 that needed to be replaced. Once i did i got a picture again.

Another Vizio due to bad regulator!