Vizio E500i-A1 No Power

[toddw65]

My new project is a Vizio E500i-A1 which does have voltages present on the power board, however, nothing happens when you push the power button. No backlight, picture or power LED.

I've annotated voltages I found on the attached pictures.

Thanks in advance for your help on this one.

Todd

[budm]

Re: Vizio E500i-A1 No Power

You do have PS-ON signal from main board to turn on the switched 12V/24V power supply but the main board is not sending the BL-ON and the Dim control signals.
You have problem on the main board.

[toddw65]

Re: Vizio E500i-A1 No Power

Thanks Bud. Is there a way to fire up the backlights to make sure they work?

[toddw65]

Re: Vizio E500i-A1 No Power

Based on other posts here, I pulled the wire from the ON/OFF pin on CN9102. Then I used a 1k resistor to jump from 5v to ON/OFF. All the voltages on the power board come up to what they are supposed to be and there is 24v at CN803 on the LED driver board. It's interesting that each of the VLED+ pins have 43v on them which seems low based on posts I've read here. I also powered the unit down and read the initial voltage at VLED+ and it doesn't go higher then 43v.

[budm]

Re: Vizio E500i-A1 No Power

Based on other posts here, I pulled the wire from the ON/OFF pin on CN9102. Then I used a 1k resistor to jump from 5v to ON/OFF. All the voltages on the power board come up to what they are supposed to be and there is 24v at CN803 on the LED driver board. It's interesting that each of the VLED+ pins have 43v on them which seems low based on posts I've read here. I also powered the unit down and read the initial voltage at VLED+ and it doesn't go higher then 43v.

So you left the connector between the main board and the power supply board in place but remove the ON/OFF pin to force on the backlights but the VLED+ did not jump up from 43V? If that is the case the Boost converter is not active to provide higher Voltage to drive the LEDs.

[toddw65]

Re: Vizio E500i-A1 No Power

That's correct. Everything hooked up except the single wire the ON/OFF pin.

[budm]

Re: Vizio E500i-A1 No Power

That means we will have to trace out the LED driver circuits next.

[RobII]

Re: Vizio E500i-A1 No Power

Sorry to bump an old thread. I have the same tv with the exact same problem. Were you able to diagnose this and get it fixed?

edit: Anyone have a link to the service manual?

[toddw65]

Re: Vizio E500i-A1 No Power

I ended up replacing the main board and its still going strong.

[RobII]

Re: Vizio E500i-A1 No Power

Good to know. I have a main board coming tomorrow. Thanks for the update.

[toddw65]

Re: Vizio E500i-A1 No Power

No problem. Good luck!

[RobII]

Re: Vizio E500i-A1 No Power

Success! It was the main board. I ordered the full repair kit from Shopjimmy as it was only $20 more than just getting the main board by itself. TV looks great!

[CRTLED]

Re: Vizio E500i-A1 No Power

I am trouble shooting the same unit, Vizio E500i-A1 remotely.

So far, PS and MB have been replaced with known good units, no change.

The "Power" LED on the lower left comes on then fades out while turning TV on.

I will be near the TV next week and can check voltages, any other thoughts?