VIZIO E470i-A0 no backlight

[ChuckAZ]

I feel like this subject has been around for some time, but I have a question.
I understand the LED driver voltage output should be 100v, my set has vout1 and vout2 at 66.8v with no difference if the LED connector is connected or not. Does the power supply sense a fault and reduce the voltage/current output to protect itself or is this power supply bad? I know I have some bad LED strips. Just want to troubleshoot before replacing everything. One additional note, connecting the meter to the pins before turning on the set and then powering it up - provides 100v for about 1 second then drops to 66.8

Does anyone have a schematic for this power supply?

[dick_barton]

Re: VIZIO E470i-A0 no backlight

Sounds like you just have bad leds, If the led driver detects a fault, open circuit led or high current due to shorted leds, then it switches off the boost supply and the led voltage drops. That is what you are seeing. Initially rises to 100V then drops quickly.

[SLK001]

Re: VIZIO E470i-A0 no backlight

Fix your backlight and you should be back in business.