[Vizio XVT3D554SV] Orange logo, won't power on

[nelliott500]

I've seen one other thread about this same issue (https://www.badcaps.net/forum/showthread.php?t=59325) but there was no resolution.

Same symptoms as the other thread (orange Vizio light, nothing happens when pressing power button, power board fuse is good, getting 5.1v at connectors, can't get 12v anywhere, no reading at the voltage regulator on main board).

I did notice a dark spot on the power board (picture attached). Pulled the board and RS202 doesn't look so good. I'm hoping that's a clear cut sign that this thing just needs a new power board.

Can you guys provide a little insight?

[dskall]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

Need voltages from connector that goes from power supply board to main board. Will need pin#-pin label-Pin voltage in standby-Pin voltage when pushing power button and picture of connector on power supply board.
Format:
Pin# - Pin Label - Pin Voltage standby - Pin voltage power on
1 - XXXXXXX - XXv - XXXv
2 - XXXXXXX - XXXv - XXXv
3 - XXXXXXX - XXXv - XXXv
4 - etc.

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

Pin #	Label
1	+5.1VSB
2	+5.1VSB
3	+5.1VSB
4	+5.1VSB
5	GND
6	GND
7	GND
8	GND
9	GND
10	+12V
11	+12V
12	+12V
13	Remote on/off
14	BL on/off
15	LD on/off
16	Dimming signal

For the voltage readings, I'm not 100% sure which pin is which since the connector has two rows but the pin label doesn't. I took a reading from each at the connector side and below is the readings. I'm getting the same at standby and when pushing the power button (no remote - just the stupid power/menu combo thing on the side).

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

There's also a smaller 4 pin connector CN204 from power to main board that says it's GND [1 - 2] and +18V [3 - 4]. I'm reading 0.3v on pins 3 and 4 at standby and pushing the power button.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

With your meter in ohms mode can you measure the resistance of RS202 (1K Ohm) and also check the resistance between the two legs on the left then right side of IC202

[dskall]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

I believe your top row is odd bottom row is even numbers

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

With your meter in ohms mode can you measure the resistance of RS202 (1K Ohm) and also check the resistance between the two legs on the left then right side of IC202

I'm seeing 994 for RS202.

IC202 right side (I believe based on text direction on top of the board) is reading 1454 and left side is 0.

I believe your top row is odd bottom row is even numbers

I think you're right. That was pretty obvious now that I look at it again.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

I'm seeing 994 for RS202.
IC202 right side (I believe based on text direction on top of the board) is reading 1454 and left side is 0.

994 ohms for RS202 is fine.
IC202 should not read 0 ohms so either that IC is short circuit between those two pins or something attached to those pins is short circuit. What is the part number.

With your meter set to diode mode set switched off can you check between the 3 pins of ICS201 and give the readings between K/A/R. Cant really read the letters off your photo's. Also what is its part number.

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

If I have my multimeter set to 20k ohms I'm getting a reading on both pairs of legs for IC202 (7.17 right, 11.78 left). Set to 2000 ohms and I still only get a reading on the right pair. Am I doing something wrong? Using the multimeter incorrectly?

For IC202 the part # is NEC 2561A WK021.

ICS201 (part # KIA 431A 026) readings:

R - A: 1288
R - K: 942
A - K: 680

I also find it odd that I'm having trouble getting a reading from the top of the board on both IC202 and ICS201. Readings are fine from the bottom but I rarely get a reading from the top.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

Here is the information on the opto-isolator. Can you identify the pins number you say on the left side read 0 ohms Pin 1 of the opto-isolator has the dot nearest it or the line running down it alongside pin 1 & 2.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

Here is the information on the opto-isolator. Can you identify the pins number you say on the left side read 0 ohms Pin 1 of the opto-isolator has the dot nearest it or the line running down it alongside pin 1 & 2.

I see that post#1, picture 5 shows pin 1 of the Opto-isolator marked on the circuit board. Is it the two pins closest to RS202 or the other side that measured 0 ohms.

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

The other side. Pins closest to RS202 are getting a reading.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

You need to unsolder and remove the opto-isolator. Check across the solder pads when you have removed it to see if you still have a short (0 ohms). If the 0 ohms is only across the pins of the opto-isolator then that needs to be replaced.
Can you post a focused photo (underside of board) so that the connections from the opto can be traced.

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

www.shopjimmy.com has a pretty good picture of the underside - probably better than I would be able to take.

http://assets.shopjimmy.com/media/ca...870-bottom.jpg

If that isn't quite clear enough I'll see what I can do.

I'll work on desoldering the opto-isolator as soon as I can.

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

I've got the opto-isolator removed but I think I gave some bad information before and it didn't hit me until right now. The right side of the opto-isolator is showing ~1454 ohms but the left side isn't showing 0 - it's showing no continuity at all. That was confusion on my end.

With the opto removed both pairs of solder pads are showing no continuity and I'm getting the same readings on the opto as before.

Thankfully it's easy enough to reinstall this opto-isolator. Hopefully that information is more helpful.

I did get more pictures of the back of the board but I'm not sure how helpful they'll be. They're attached.

[dick_barton]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

With the set in standby measure the voltage between pins 1 & 2 and also between pins 3 & 4 and then do the same when you take it out of standby.
Pin numbers as shown in post#10

[budm]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

https://www.badcaps.net/forum/attach...0&d=1491156770
Connector back in place.
As you can see from the picture, there a pin labeled with '1' next to it, that will be pin 1, the pin above it will be pin 3, and above pin 3 is pin 5, so basically the left column is for ODD number pin, the EVEN column pins you will have to measure the reading from the back side of the connector using skinny probe.
Right now you have standby Voltage, so we need to find out if you have >2VDC on PS-ON (REMOTE ON/OFF) pin 13 to turn on the rest of the power supply or not, you can easily get to pin 13 from the top side of the board.
It also looks like the LED in the OPTO is bad. What resistance do you get on RS102?

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

With the set in standby measure the voltage between pins 1 & 2 and also between pins 3 & 4 and then do the same when you take it out of standby.
Pin numbers as shown in post#10

Opto is soldered in again. No voltage across either pair with power or without.

https://www.badcaps.net/forum/attach...0&d=1491156770
Connector back in place.
As you can see from the picture, there a pin labeled with '1' next to it, that will be pin 1, the pin above it will be pin 3, and above pin 3 is pin 5, so basically the left column is for ODD number pin, the EVEN column pins you will have to measure the reading from the back side of the connector using skinny probe.
Right now you have standby Voltage, so we need to find out if you have >2VDC on PS-ON (REMOTE ON/OFF) pin 13 to turn on the rest of the power supply or not, you can easily get to pin 13 from the top side of the board.
It also looks like the LED in the OPTO is bad. What resistance do you get on RS102?

Great explanation for the pins. Thanks.

No voltage on pin 13 in standby or pressing the power button. I don't have the remote right now to test with, just the power button.

[budm]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

No PS-ON present when TV is turned ON then the rest of the power supplies will not be on to run the TV, something is stopping the main board from sending out the command to turn on the power supply.
But it looks like you have problem with the power supply in that section where the burnt resistor is, as you can see there are two identical circuits with the same circuit setup,

[nelliott500]

Re: [Vizio XVT3D554SV] Orange logo, won't power on

So the issue could still be either the power or main board?

This was not originally my TV - my sister owned it and it would occasionally shut off and require a period of cool down before it turned on again. This last time it finally didn't turn on. As far as I'm aware they did not have any issues with the TV powering on other than after an abrupt shut down like this.

It seems that there was/is clearly some issue with the power board with the dark spot. But you're right that it's strange that the power board does not receive a signal to attempt to turn on the power supply. I wish I had the remote for it instead of just the "jag wheel".

I can get a power board for $90 on eBay which is tempting to take a chance.