vizio vo42oe 42"lcd heat problem

[Grn94hatch]

Ive searched all over the net and have learned some of the people on have the answsers. I have a 42" vizio that will power up and turn on, but after about 15 minutes of watching tv it goes black. Then it turns on and off and so on just like alot of others on here that seem to have the same problem. The tv doesnt make any popping noise, I have looked at both boards very closely and all the caps look fine no swelling or bulging. Someone on another site had said it was a heat sink problem, but that didnt seem to make any sense to me but then again I dont repair electronics for a living. So if any one has some input or the answer I would really appreciate the help! Thanks!

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

When you say,"turns on and off and so on", Does that include the "Vizio" logo on the front of the tv changing colors? Also, could you attach a few good photos of the boards, as this would be the best way to get better responses?

[rmoody]

Re: vizio vo42oe 42"lcd heat problem

sounds like you need some new inverters

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

These are the pics that i took, and the vizio logo does not change colors.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

I put the tv back together so i didnt have parts all over the dining room, i pluged it in and turned it on. Now its just the back light no picture or sound, could my first problem have cause the caps to go bad now?

[PlainBill]

Re: vizio vo42oe 42"lcd heat problem

I put the tv back together so i didnt have parts all over the dining room, i pluged it in and turned it on. Now its just the back light no picture or sound, could my first problem have cause the caps to go bad now?

Not likely. Two likely causes - you forgot to hook up a cable somewhere - or there is a bad solder joint that was opening up when it got hot. Now it was jostled enough it is always open.

PlainBill

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

I never took out the boards I just took the back cover off and the metal cover off of the video board. Does that change your answer at all Plain Bill

[Dgtech]

Re: vizio vo42oe 42"lcd heat problem

Do you smell any electronic smells when it heats up? Here's something to try too if possible. Turn the brightness, contrast, or backlight, all down to about 50%. I've seen some sets where the heat comes from the inverter section driving the backlights hard.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

I didnt smell anything, like the burned electronics smell. In the thread topic I said heat problem, it actually was more like when the tv finally warmed up it would turn off and on off and on. Then like I said earlier in the thread now its just back light no on and off just solid backlight.

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

I agree with PlainBill, I'm thinking a bad solder joint or a loose connection. It probably can be found on the main board.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

So pull the main board and take a look for a bad solder joint, if I find one just re-solder it?

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

So pull the main board and take a look for a bad solder joint, if I find one just re-solder it?

In short, yes.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

There is a fuse right next the where the power cord plugs in, the fuse has a red line around it???

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

I think you are looking at the wrong board. I modified the power supply/inverter board photo you attached to show the fuse I think you are looking at. The main board is the one in which you removed the cover and what you called "video board". It is greenish in color. Take a look at this board for loose connections or bad solder joints.

Since you have a back light, this would imply that there is nothing wrong with the power supply providing power to the inverter section of that board. You can check the voltages going to the main board with a meter. On the power supply (yellowish board), the voltages are listed near the connector going to the main board. I hope this clears up some confusion.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

Now the tv wont turn on at all?

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

I have looked at both bords and all the solder joints look fine to me, Im not sure what to do next. should i just look for new boards?

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

With all boards connected back together, does the "VIZIO" logo on the front light up when the unit is plugged in?

If yes, that indicates that 5v standby voltage is good.

If no, main fuse could be blown and/or 5v standby voltage is not getting to the main board. Check the labeled voltages on power supply. See attachment on where to check.

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

Yes it lights up orange when plugged in, ill check the voltage as soon as I get home and ill post my results. Thanks

[Grn94hatch]

Re: vizio vo42oe 42"lcd heat problem

I checked with my multi-meter and I got 10.6 volts on all 3 stand by voltaltage terminals. And 0 on all the others.

[1beertap]

Re: vizio vo42oe 42"lcd heat problem

When you press the power button or remote to turn on tv, does the "VIZIO" logo go from orange to white? Does it stay white?