Vizio E370VA wont turn on

[nbnb]

I have a Vizio E370VA that won't turn on. It was working fine until I didn't use it for several weeks. When I press the power button, the Vizio logo below the screen gets bright for about 1 second and then dims. The screen remains blank and the Vizio screen logo never displays.

I have tried unplugging the set, holding the power button for 30 seconds, and then powering it up. That didn't help.

I pulled the back off and measured 3.66 volts on the standby port labeled 5V. I disconnected the main board from the power board and then the 5V port read 5.25 volts. Does this indicate that the power board is bad? Or, does this indicate that the power board is operating correctly and that the main board may be bad?

Any ideas on how to fix this?

[R_J]

Re: Vizio E370VA wont turn on

Did the standby voltage change when you turned the tv ON? Also check if you have the PS_ON voltage when the power buttonis pressed. The +5v could be low (3.6v) in standby but would increase when the PS_ON is high. If the voltage stays low, check C952, C954, C958 and C960

[nbnb]

Re: Vizio E370VA wont turn on

Thanks for your reply. PS_ON voltage is 3.60 volts when the TV is off. When I turned the TV on, PS_ON voltage went to 0 volts and the standby voltage went to 5.16 volts. Also, the 24 volt pins measure 24.6 when off and 0 volts when the tv is on. The 12 volt pins measure 12 volts when off and 0 volts when on.

Is the PS_ON voltage supposed to go to 0? What else can I check to narrow down the problem?

Did the standby voltage change when you turned the tv ON? Also check if you have the PS_ON voltage when the power buttonis pressed. The +5v could be low (3.6v) in standby but would increase when the PS_ON is high. If the voltage stays low, check C952, C954, C958 and C960

[R_J]

Re: Vizio E370VA wont turn on

I think you have the voltages backwards, When the tv is ON The PS-ON voltage will high (3.6v) . When the TV is OFF the +12 & +24v will be 0. When they are at +12 & +24V the tv is ON.
Post some pictures of the complete rear of the tv so we can see what we are dealing with. You may have a backlight issue. Try shining a flashlight at the screen and press the menu button to see if you can see anything on the screen. You could also try connecting a HDMI source and see if the tv goues to that input and gives you sound etc.

[nbnb]

Re: Vizio E370VA wont turn on

I plugged it in (so the TV should be off) and get the following voltages:

3.60 (5v)
3.60 (ps/on)
24.6 (24v)
12 (12v)

When plugged in, the vizio bezel logo glows dimly.

Pressing the power button, the bezel logo gets bright for about a second before dimming. I get the following voltages:

5.16 (5V)
0 (ps/on)
0 (24V)
0 (12V).

If I press the power button again, the bezel logo darkens and then returns to a dim state.

I don't see anything when using a flashlight to illuminate the screen. I don't get any sound. I never see the screen startup logo. It's as if the TV is not turning on.

Several pictures are attached.

I think you have the voltages backwards, When the tv is ON The PS-ON voltage will high (3.6v) . When the TV is OFF the +12 & +24v will be 0. When they are at +12 & +24V the tv is ON.
Post some pictures of the complete rear of the tv so we can see what we are dealing with. You may have a backlight issue. Try shining a flashlight at the screen and press the menu button to see if you can see anything on the screen. You could also try connecting a HDMI source and see if the tv goues to that input and gives you sound etc.

[budm]

Re: Vizio E370VA wont turn on

"3.60 (5v)
0 (ps/on) This cannot be 0V and still having switched 12V and 24v to be on.
24.6 (24v)
12 (12v)"

[nbnb]

Re: Vizio E370VA wont turn on

Thanks, and sorry. You are right. I had the correct voltage in post #3 for when the TV is off. I edited my post to note that it is 3.6 volts.

"3.60 (5v)
0 (ps/on) This cannot be 0V and still having switched 12V and 24v to be on.
24.6 (24v)
12 (12v)"

[R_J]

Re: Vizio E370VA wont turn on

If you look at the inverter board (small board on the right in pic#1) , there is a small led (LED1)that should light for a few seconds then fade out when the tv is first turned on. If this does not happen, When there is +24 volts at the inverter, check the voltage on both sies of the fuse (F1) and also check the voltages on pins 14,13 & 12.
Pin 12 is the inverter on/off

[nbnb]

Re: Vizio E370VA wont turn on

The LED1 does not light up at all. When I have 24.6 volts on PIN 1 of the inverter, the F1 fuse measured 24.7 volts on both sides of the fuse. Pin 14 was 0.28V, pin 13 was 2.46V, pin 12 was 0.09V, and pin 11 was 0.10V.

I attached some pictures of the inverter board with the cover off.

If you look at the inverter board (small board on the right in pic#1) , there is a small led (LED1)that should light for a few seconds then fade out when the tv is first turned on. If this does not happen, When there is +24 volts at the inverter, check the voltage on both sies of the fuse (F1) and also check the voltages on pins 14,13 & 12.
Pin 12 is the inverter on/off

[budm]

Re: Vizio E370VA wont turn on

https://www.badcaps.net/forum/attach...0&d=1573102972
pin 13 (Dimmer control) was 2.46V,
pin 12 (BL-ON) was 0.09V
You do not have BL-ON to turn on backlights circuits.

[nbnb]

Re: Vizio E370VA wont turn on

Does that mean the inverter board is bad and should be replaced?

https://www.badcaps.net/forum/attach...0&d=1573102972
pin 13 (Dimmer control) was 2.46V,
pin 12 (BL-ON) was 0.09V
You do not have BL-ON to turn on backlights circuits.

[budm]

Re: Vizio E370VA wont turn on

PS-ON, BL-ON, DIM signals are from the main board.
You can try forcing on the inverter board by disconnecting the BL-ON wire from the inverter board connector then use 1K resistor between the BL-ON pin of the Inverter board and the Standby 5V pin to force on the inverter board.
You should read Basic LCD TV and monitor troubleshooting guide.

[budm]

Re: Vizio E370VA wont turn on

BTW, I do not know which main board you have, but shopjiimy is EEPROM for this TV model, see the description of what the EEPROM will fix.
https://www.shopjimmy.com/catalogsea...q=Vizio+E370VA

[nbnb]

Re: Vizio E370VA wont turn on

Thanks for your reply.

[R_J]

Re: Vizio E370VA wont turn on

If ypou want to check the power supply and inverter/backlights. disconnect the cable from the power supply going to the main board. Then connect about a 1K resistor between the +5V (pin 12 or 11) and pin1 (ON/OFF) then place another 1K resistor between +5V and pin10 (or you can short between pins 10&11) Then plug in the tv. this should turn on the power supply and the backlight (there will not be a picture)
You may also need a third 1K resistor between +5 and pin2 (DIM) if the backlights don't turn on

[nbnb]

Re: Vizio E370VA wont turn on

If I do this, and the backlight turns on, does it indicate that the power supply and inverter/backlights are good and that the problem is with the main board? Or, could the problem still be with the power supply?

If ypou want to check the power supply and inverter/backlights. disconnect the cable from the power supply going to the main board. Then connect about a 1K resistor between the +5V (pin 12 or 11) and pin1 (ON/OFF) then place another 1K resistor between +5V and pin10 (or you can short between pins 10&11) Then plug in the tv. this should turn on the power supply and the backlight (there will not be a picture)
You may also need a third 1K resistor between +5 and pin2 (DIM) if the backlights don't turn on

[R_J]

Re: Vizio E370VA wont turn on

Yes, that test would turn on the power supply, the inverter and the backlights. That would indicate the main board is at fault and could point to a corrupt eeprom.
If you have a can of freeze spray or an inverted can of canned air, you can try this to see if the eeprom may or may not be the issue:
Unplug the tv, freeze the eeprom ic, wait 10~15 seconds, plug in the tv and see if turns on.
If this test does work the fault is with the eeprom ic and the rest of the main board is likely ok. If this does'nt work you could still have a faulty eeprom
Being a Vizio and this model I would highly suspect a corrupt eeprom ic

[nbnb]

Re: Vizio E370VA wont turn on

Thank you.