Transistor for TV problems

[stj]

Re: Transistor for TV problems

same part number, but it does not need to be the same maker.

so an AZ1117-3.3 could be swapped for an LM1117-3.3 for example.
if it's a 1117 you just need to match the voltage.

[Cue]

Re: Transistor for TV problems

This might be a dumb question but do i have to get the exact same Voltage regulator model number or just the same volt number if a voltage regulator tested bad?

[budm]

Re: Transistor for TV problems

https://www.badcaps.net/forum/showth...999#post300999

[stj]

Re: Transistor for TV problems

yes,
3 pins usually.
one is the input, one is output and one is either ground, or goes through resistors to set the output voltage.

go download a datasheet for a 1117 regulator.
https://duckduckgo.com/?q=1117+datas...t-wt&kv=1&kh=1

[Cue]

Re: Transistor for TV problems

Yes, there are regulator ICs on the main board.
Your TV has more than one versions so I do not know exact one that you have, they are not cheap.
http://www.shopjimmy.com/catalogsear...q=Vizio+E470VL

Can I test a voltage regulator IC in circuit?

[budm]

Re: Transistor for TV problems

Yes, there are regulator ICs on the main board.
Your TV has more than one versions so I do not know exact one that you have, they are not cheap.
http://www.shopjimmy.com/catalogsear...q=Vizio+E470VL

[Cue]

Re: Transistor for TV problems

They can have the same body case style but the electrical function are not the same.
Voltage regulator IC is an integrated circuit contain many transistors, diodes, resistor, caps, etc.

Is there a voltage regulator on the vizio main board? Or only on the power board?

[budm]

Re: Transistor for TV problems

They can have the same body case style but the electrical function are not the same.
Voltage regulator IC is an integrated circuit contain many transistors, diodes, resistor, caps, etc.

[Cue]

Re: Transistor for TV problems

My personal experience on almost every Vizio main board from this era is as follows:

If the screen lights up briefly with the vizio logo then freezes, the eeprom usually fixes it. If there is no backlight as you've describes but the logo changes color, then 95% + of the time it's going to be one or more bad voltage regulators.

What's the difference between a voltage regulator and a transistor? They both look the same right?

[aaronwt6]

Re: Transistor for TV problems

My personal experience on almost every Vizio main board from this era is as follows:

If the screen lights up briefly with the vizio logo then freezes, the eeprom usually fixes it. If there is no backlight as you've describes but the logo changes color, then 95% + of the time it's going to be one or more bad voltage regulators.

[budm]

Re: Transistor for TV problems

I am not sure if this EEPROM problem or not, look at shopjimmy website to see.
The metal shield is for the main processor.

[Cue]

Re: Transistor for TV problems

Can a eeprom fix this issue? And what's under that metal rectangle in the middle of the main board?

[budm]

Re: Transistor for TV problems

OK, then the problem is on the main board and will require more troubleshooting.

[Cue]

Re: Transistor for TV problems

Yes the TV was on when I did the readings. Here's the pics

[budm]

Re: Transistor for TV problems

Did I measure it correctly?

It is not showing as shorted circuit, using Ohm meter can only do so much for testing the MOSFET, but this MOSFET has nothing to do with what the TV is doing right now, it is the main board that is not sending the signals to turn on the power supply board and the inverter board but we need to know if those Voltage readings are made with the power switch is activated or not, that is VERY IMPORTANT info I need to know.

[Cue]

Re: Transistor for TV problems

Are these readings with the power switch activated? If it is activated, then the main board is the problem.
https://www.badcaps.net/forum/attach...7&d=1431658037

We will need good clear pictures of the whole back side of the TV to see all the boards.

OK, I will tomorrow

[Cue]

Re: Transistor for TV problems

That is body diode of the MOSFET you are seeing, the Cathode of the Diode is connected to the Drain pin (middle pin), the Anode is connected to the Source pin (right pin), this is N-CH MOSFET.

Did I measure it correctly?

[budm]

Re: Transistor for TV problems

Yeah, no picture and no back light, I tried the flashlight test I didn't see anything. Here's the pictures

Are these readings with the power switch activated? If it is activated, then the main board is the problem.
https://www.badcaps.net/forum/attach...7&d=1431658037

We will need good clear pictures of the whole back side of the TV to see all the boards.

[budm]

Re: Transistor for TV problems

I had the negative lead in the middle, I put the positive lead on the left side It tested OL and on the right side it tested .259

That is body diode of the MOSFET you are seeing, the Cathode of the Diode is connected to the Drain pin (middle pin), the Anode is connected to the Source pin (right pin), this is N-CH MOSFET.

[Cue]

Re: Transistor for TV problems

Yeah, no picture and no back light, I tried the flashlight test I didn't see anything. Here's the pictures