Envision LCD Capacitor Advice

[TomInTX]

This relates to my son's Envision G2016WA1, LCD monitor.

A little background, I am mechanically inclined and fix my own cars/trucks, but have not gotten deep into electrical components before.

Last night my sons Envision monitor starting to show the common problem of turning on but going off after 2 seconds, the green power light stays on. If you turn it off and then back it will go another 2 seconds then shut off again.

Reading the forums this looks like a common problem. I also read about a test whereby you shine a bright flash light to see if you can see the windows background. With his, you cannot see anything it is just black.

I would really like to show my son that you can fix electronic things and not have to buy something just because it isn't working.

I am asking for some advice with this problem.


We have it open already, and I'm not an expert to tell if any of the caps are swollen, so I included pictures A,B, and C. Are any of these caps swollen, will replacing these fix the problem?

Thanks in advance,

Tom

[budm]

Re: Envision LCD Capacitor Advice

I do not see any bulging caps, but bad cap can look normal.
Since you do have 2-second to black, it can be the MOSFETS that drive those two black high voltage inverter transformers, bad winding on the inverter transformers, cold/bad solder joints, bad lamps. etc.
Can we see good clear pictures of the bottom side of the board?

[Agent24]

Re: Envision LCD Capacitor Advice

I can't see any in those photos that are bulging - but that doesn't mean they are OK.

They appear to be Hermei brand which are not very good, and I have personally replaced some of them in an LCD monitor that looked OK but were bad, so it's a bit higher than average chance they are the problem.

If you have an ESR meter you can easily check them against the datasheet to see if they are in specification... but probably you don't have one and since they're low quality you might as well just replace them anyway.

If you are unsure what to replace them with, post their details here, series, size, values etc.

Bear in mind that replacing them may not solve the problem, and you may need to do more in-depth troubleshooting.

[TomInTX]

Re: Envision LCD Capacitor Advice

budm and Agent24,

Thank you so much for the fast replies. Another thing I noticed is that when I press the power button and during the two seconds it works, there is a faint buzzing sound coming from the area where the left speaker is, I don't know if it normally makes this sound, but it goes away when the screen goes black.

I don't have an ESR meter to check them, I will write down all their values and post them here.

I took more detailed pictures, as requested, of all four sections of the board they are attached below.

Tom

[SteveNielsen]

Re: Envision LCD Capacitor Advice

Please remove the board and get some clear pictures of the bottom of the board too.

[TomInTX]

Re: Envision LCD Capacitor Advice

Here are pictures of the backside of the board as requested. Tom