Vizio e500i-b1 no turn on standby light fades out in 5 sec.

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

BTW, do you have any spare diode around that you can do the resistance test in 2K Ohms scale?

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

We need the P/N of the PFC IC9801 so we can get the spec sheet to find out if it has VCC to run or not.

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Here's what my meter can do, no spare diode

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Looks like ld7591gs
1529de

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Another guy working on same TV has way more filter cap voltage. I guess I don't have the boost power.

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

OK, you need to find out what VCC you have between the VCC pin and the GND pin of the LD7591. It needs 12V to start.
The 300 Something Ohms reading still bugging me.
It reminds me about this thread.
https://www.badcaps.net/forum/showthread.php?t=56821

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

OK I'll get the voltage today is that in standby or powered on.

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

I get .3 volts on vcc to ground on ic in standby and power on

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

I get .3 volts on vcc to ground on ic in standby and power on

OK, test the resistance between the VCC pin and GND to see what you have, and then need to trace the VCC pin to see where it goes to, it should go to the switched Transistor some where on the board.

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Red + on vcc and black- on ground on it in 20K scale is 0 or open , if I reverse leads I get 7.2

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Red + on vcc and black- on ground on it in 20K scale is 0 or open , if I reverse leads I get 7.2

OK then, circuit tracing will be the next step.

[snake91876]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

So I'm looking for path of vcc leading to switching transistor and look in for any break in circuit.

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

So I'm looking for path of vcc leading to switching transistor and look in for any break in circuit.

Break in the circuit, the transistor is not being turn on, bad transistor, no Voltage feeding the transistor, etc.

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

BTW, just to make sure, you did test the VCC pin 8 when PS-ON is present, right?

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

BTW, I post the wrong P/N of your board, it should be ADTVD3613XA6.
http://www.shopjimmy.com/vizio-adtvd...upply-unit.htm

Pictures provided by shopjimmy

I will see if I can trace out pin 8 of the PFC IC to see where it goes.

[budm]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

OK, the switched Transistor that supplies the Voltage for the VCC of the PFC IC and the switched SMPS IC is Q9101.
The Voltage feeding the switched Transistor Q9101 Collector is generated from the AUX winding of the stby power transformer, that same Voltage is also used for the running Voltage for the stby SMPS IC.
The output Voltage is on the Emitter pin of Q9101.
Q9101 is turned on when the OTPO couple IC9104 is turned on when PS-ON is present.
So there you go, start probing.

[brian the hack]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

FWIW I had the same unit with the same symptom brought to me. I replaced ic 9101 under heat sink (on power supply) and so far so good. gonna watch it for a day or so before sending it back home. I will update if it crashes and burns.

[Rmasters3]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

What ended up being the fix for this set? Thanks

[jhrsmail]

Re: Vizio e500i-b1 no turn on standby light fades out in 5 sec.

Yes, what was the fix? Broke down, elementary style..