Vizio Model VO 320E not working

[Don Umphrey]

I have a Vizio model vo320e 32inch TV which has no picture, or sound and has a black screen . The Vizio name logo is orange in stand by and white when turned on . The only side button that will respond is the on/off button. When turned on there is a blue lite coming from each board. The blue lite on the power supply/inverter back lite board stays lite longer (several seconds) before going out. The blue lite coming from the main board goes out much quicker. I have taken voltage reading at the wire harness plug connectors where the power supply board connect to the main board. The reading at the three 5volt pins and three 12volt pins were good. At the pin marked on/off I get a voltage reading of .1 volts in the off position and 2.87 volts is the on position. I have also have taken voltage reading at the large capacitor which lays on it side on the power supply/ inverter board. I got 167 volts turned off and 390 volts turned on. A visual look at the boards through a magnify glass shows no signs of bulging caps or signs of any over heated components. When talking with Vizio they said I would need a new LCD screen with back lite. Do you think I am getting a right answer ? I hate the thought of throwing the TV out if it was something less expensive to repair. Thank you Don

[Mr Bill]

Re: Vizio Model VO 320E not working

Does the tv turn on and stay on or does it quickly shut back off?

[Don Umphrey]

Re: Vizio Model VO 320E not working

Does the tv turn on and stay on or does it quickly shut back off?

When I turn it on the vizio logo goes from orange to white and stays white until I shut it off.

[Don Umphrey]

Re: Vizio Model VO 320E not working

[Mr Bill]

Re: Vizio Model VO 320E not working

Do you have 24v coming from the power supply when it's on?

[Don Umphrey]

Re: Vizio Model VO 320E not working

Do you have 24v coming from the power supply when it's on?

Mr Bill I wish that I had the knowledge to know where to take the reading but I guess I don't. I can't get a reading of 24v any where on the power supply/ inverter board. The voltage from the pins for 5v and 12v read correctly.

[tom66]

Re: Vizio Model VO 320E not working

This PSU doesn't use a 24V supply, it drives the backlight tubes directly with around 700V. (Do not try to measure this though - you could damage your meter.)

[Don Umphrey]

Re: Vizio Model VO 320E not working

This PSU doesn't use a 24V supply, it drives the backlight tubes directly with around 700V. (Do not try to measure this though - you could damage your meter.)

Should the high voltage(950volts) as mark on the circuit board be coming from the wires coming from the two flat transformers. One wire from each transformer. These wires look to be contacted to the lcd screen. I set my meter on 1000 v even being warned not to but I don't think that I am getting any voltage from these transformers.

[tom66]

Re: Vizio Model VO 320E not working

It's 1040V according to the label due to it being an 803 unit.

The reason you shouldn't try to measure it is because it's at around 50kHz and at 1040V. Not only could you damage the meter (it's only rated for 50/60Hz AC) but you risk electric shock as most cheaper meters do not have adequate insulation at 1000V. Also, it pulses the tubes with about 2000V to get initial ignition.

In general if you get any output from there the tubes will light up, even if the TV turns the backlight off a few seconds later due to a broken tube.

[Don Umphrey]

Re: Vizio Model VO 320E not working

It's 1040V according to the label due to it being an 803 unit.

The reason you shouldn't try to measure it is because it's at around 50kHz and at 1040V. Not only could you damage the meter (it's only rated for 50/60Hz AC) but you risk electric shock as most cheaper meters do not have adequate insulation at 1000V. Also, it pulses the tubes with about 2000V to get initial ignition.

In general if you get any output from there the tubes will light up, even if the TV turns the backlight off a few seconds later due to a broken tube.

I guess I lucked out as nothing happened at all. what would keep it from putting out the high voltage? Could it be a bad lcd screen as the tech. from Vizio said?

[Mr Bill]

Re: Vizio Model VO 320E not working

Mr Bill I wish that I had the knowledge to know where to take the reading but I guess I don't. I can't get a reading of 24v any where on the power supply/ inverter board. The voltage from the pins for 5v and 12v read correctly.

I guess i should look at all the pictures before i post

Your tcon board might send a signal that tells the power supply to turn on the backlights. That would be the only thing i can think of as to why vizio would say you would need a new panel. Post a picture of your tcon. You might be lucky and just the fuse on it blew.