Vizio D650i-B2

[6of1]

Just need some verification, I think..

Like in this video (skip to 1:30) I tested for 5V on pins 1 & 2.

With the harness connected I get numbers bouncing all over (between 0-1.9v).
With the harness removed I get 5v steady.

Does this still mean it is the PS?

[nomoresonys]

Re: Vizio D650i-B2

Can you throw up some good clear pics. of each individual board and one of how they are all connected? a good start is check all the pins on connector from maionboard to powerboard on powerboard side with harness connected, there should be a little map/legend of the expected voltages on the board near the connector, you want to check with tv plugged in and tv off make note of voltages then turn tv on and make note, report voltages here, example: pin 1 pson o volts standby 5 volts with tv on.

[6of1]

Re: Vizio D650i-B2

The voltages are steady 5v when the main board is disconnected.

The power button does nothing, no clicks..

[nomoresonys]

Re: Vizio D650i-B2

If this is your board, maybe start with checking connector CN101 pins 1 thru 4 and 11 thru 15 and follow testing as described in post # 2. You need to test more than just the 5 volt pins, write down readings as described and report them. https://www.shopjimmy.com/vizio-56-0...upply-unit.htm

[nomoresonys]

Re: Vizio D650i-B2

Seems like a mainboard issue?

[6of1]

Re: Vizio D650i-B2

See pic for voltage readings.

I’m not sure, that’s why I’m here

[budm]

Re: Vizio D650i-B2

1) Can we see the pictures of the whole back side of the TV showing all the boards?
2) Try having just the main board and the power supply board connected together and NOTHING else connected to the main board then plug the TV into the AC outlet to see if the 5VSTBY will be stable at 5V or not.
3) The problem may be the 5VSTBY power supply is bad (bad caps, I.E. startup/running caps which there are two of them in the hot side close to the SMPS IC in the STBY power supply section) or it is being loaded down too much so it goes into startup/shutdown mode.
4) We may have to use dummy load on the 5VSTBY to see if it can handle the load or not.

[6of1]

Re: Vizio D650i-B2

Ok, I disconnected everything from the main board except the power supply harness, plugged in and the standby 5v was steady at 5.03v

Attached the pic of back.

[budm]

Re: Vizio D650i-B2

Ok, I disconnected everything from the main board except the power supply harness, plugged in and the standby 5v was steady at 5.03v

Attached the pic of back.

OK, so with just MAIN board and power supply connected, the 5VSTBY is OK, so try connecting other boards to the main board one at a time and see which one will cause the 5VSTBY to go down.

[6of1]

Re: Vizio D650i-B2

Ok, well that sorta worked. Don’t know what it means exactly but.. Everything plugged in except the IR board and the tv works with a stable 5v standby. Just obviously can’t change channels or volume, lol.

[nomoresonys]

Re: Vizio D650i-B2

So when you plug ir sensor back in, you get no steady 5 volt?

[6of1]

Re: Vizio D650i-B2

So when you plug ir sensor back in, you get no steady 5 volt?

Yes

[budm]

Re: Vizio D650i-B2

Show us the pictures of the IR board (top and bottom sides) and also start checking the resistance of the capacitors on that board to see if any one of them show low resistance reading. Typical failure will be shorted MLCC.

Is this your board?
https://www.shopjimmy.com/vizio-55-7...ir-sensor.htm#

[6of1]

Re: Vizio D650i-B2

Yes that's the board.

Here's pics

[budm]

Re: Vizio D650i-B2

Well, check the resistance of the caps.

[6of1]

Re: Vizio D650i-B2

Well, check the resistance of the caps.

Not sure if I am doing this right

Ok, first question.. When you say "the caps" do you mean the pars labeled U2 & C1 on the IR board?

Is there a tutorial for testing MLCC Shorts with a multimeter and can it be done in circuit?

What I did was set my meter to 200 (ohm) and checked those 2. I got:
U2 = 1.5
C1 = 47.7

[budm]

Re: Vizio D650i-B2

You look at the silkscreen designator wrong , that will be C3 not U2.
At this point C3 looks to shorted, you need to remove it and then test the empty pads of C3 to see if it still show 1.5 Ohms or not.
Picture provided by shopjimmy.

[budm]

Re: Vizio D650i-B2

So what did you find out?

[6of1]

Re: Vizio D650i-B2

I haven’t found out anything yet other then I don’t think my soldering iron would be the best choice for removing that cap. I don’t think the tip on my weller would even fit between those 2 components.

Going to look for a finer tip today. Do you have any other suggestions?

[nomoresonys]

Re: Vizio D650i-B2

Maybe buy a replacement board, about 10-25 bucks.