Vizio VX32 Shut Down

[Chicd]

Vizio VX32 HDTV10a powers on/backlight/no picture...powers off in 30 seconds. Can power right back on w/switch but shuts down again.
Disconnected inverter board...same shut down
Standby and 12v all OK
Changed out power and main board...same problem...
What am I missing?

[budm]

Re: Vizio VX32 Shut Down

So you have backlights it means the power supply, inverter, lamps are OK.
Did you check the T-CON board?
Pictures of the whole backside of the TV so we can see what we are dealing with?

[Chicd]

Re: Vizio VX32 Shut Down

Will get photos...disconnected tcon harness...still shuts off after about 30 sec. Failed after a lightning storm/voltage spike

[budm]

Re: Vizio VX32 Shut Down

Need to check the T-CON board, when you disconnect the T-CON then the main board may sense that the T-CON is not active since there is no power for the T-CON to send OK signal back to the main board.
The new board can also be bad, you will never know what you will get from seller these day.

[Chicd]

Re: Vizio VX32 Shut Down

Did not replace tcon board...looks like it is hard to get to...

[Chicd]

Re: Vizio VX32 Shut Down

Would bad tcon cause shut down? Doesn't seem like an overheating problem since I can power it on right away...
Thanks for your help....wanted to learn about tv repair for many years...really fun but I lack the depth of knowledge to really do serious trouble shoot. I have replaced caps, vr's etc with success....

[budm]

Re: Vizio VX32 Shut Down

Yep, not easy to get to the T-CON on this model.
https://www.badcaps.net/forum/attach...9&d=1472950967
See that bare wire with two black Ferrite beads to the left of the LVDS T-CON connector and next to the Lytics cap?
See if you have 12Vdc on that exposed wire.
The 30 seconds may also be due to no Video signal detected so it goes into standby mode.

[Chicd]

Re: Vizio VX32 Shut Down

Forgot to mention that I have no led lighting on the front panel where it blinks for codes....does this model have a standby light other than the vizio logo?
I will check the voltage this AM...

[Chicd]

Re: Vizio VX32 Shut Down

Only 5.1v on that bridge wire. Some other tests...
U7 3.3/1.3/0
U33 5.1/3.3/2.1
U9 3.3/1.5/0
U8 5.1/3.3/2.1
U4 5.1/3.3/2.1
U2 5.1/3.1/2.1
This is on the board that was the replacement...original board was about the same...U7 and U9 had 0v on third leg...

[budm]

Re: Vizio VX32 Shut Down

U2 is wrong, it should have 3.3V output, you are getting 3.1V.
P/N of U7, U9?

[budm]

Re: Vizio VX32 Shut Down

BTW, you indicated that you do have 12VDC, you mean the 12VDC is present at both end of the SMD fuse for the 12V supply on the main board, right?

[Chicd]

Re: Vizio VX32 Shut Down

Is that a fuse with the ferrite beads...?
I just tested the bare wire/exposed on top...
Thought it was just a bridge wire....

[budm]

Re: Vizio VX32 Shut Down

There are two white fuses with gold ends right by the main board connector that goes to the power supply board, one fuse should have 5V, another one should have the switched 12V.

[Chicd]

Re: Vizio VX32 Shut Down

...was testing voltage on U10 #1084/0717DL and accidently shorted pin to the center one(clipped) and had an audio squeel...pulled power...turned back on and backlight stayed on until I powered it down....powered back on and shut down after 30-40 sec.
U7 is ANC1117/F0734F U9 is K1117S15/736
Still only have 5.1v on wire with ferrite beads...
Will retest the 12v fuse...

[budm]

Re: Vizio VX32 Shut Down

...was testing voltage on U10 #1084/0717DL and accidently shorted pin to the center one(clipped) and had an audio squeel...pulled power...turned back on and backlight stayed on until I powered it down....powered back on and shut down after 30-40 sec.
U7 is ANC1117/F0734F U9 is K1117S15/736
Still only have 5.1v on wire with ferrite beads...
Will retest the 12v fuse...

I am confused, so you have the 30 seconds shutdown on the original board, and also on the replacement board, but now you indicated that you had shorted out the pin on the regulator and you are now getting 30 seconds shutdown, so the shutdown happen before or after you shorted out the regulator on both board?

[Chicd]

Re: Vizio VX32 Shut Down

When pin was shorted out and I powered off....powered back on and back light remained on until I powered off after testing. Powered back on and it shut down after 30 - 40 seconds...
Both boards give 30 sec shut down...

[Chicd]

Re: Vizio VX32 Shut Down

11.9 v on both sides of fuse...
I must have a bad voltage regulator...maybe a fluke by having same problem with replacement board....was a used board...

[TechGeek]

Re: Vizio VX32 Shut Down

5V fuse tested? Exposed wire tested?

[budm]

Re: Vizio VX32 Shut Down

Right now you know that U2 has the wrong output Voltage and the PS-ON to the main board is present otherwise you will not have that switched 12VDC on the fuse on the main board.
5VSTBY fuse and Voltage is OK otherwise you will not have DCV on the regulator or the PS-ON signal.

[Chicd]

Re: Vizio VX32 Shut Down

I have repaired several Vizio, samsung, emerson, crosley and a few other brands...this one is pushing my limited knowledge of circuitry....thanks for your continued help.....I have a continuing supply of TV's and am having a good time.. Next one to tackle is a 70" vizio and a 55" Pioneer
Want to fix this little bastard first......