Vizio GV42L

[Nick4208]

The tv will not turn on, the logo will go from orange to white when its turned on and will not turn off unless I unplug it. I've done a lot of reading about the voltages regulators. I will list what I got for readings and the writing on the regulator. The reading are as if the fat tab of the regulator is on top.
U4 0.0 3.29 5.10-6LKL 17-33L
U5 4.3 1.23 3.29-AMC1117 F0631J
U6 0.0 3.30 5.10-6LKL 17-33L
U7 0.0 1.79 3.28-6L4L 17-18L
U8 0.0 3.28 5.09-6LKL 17-33L
U9 0.0 1.79 3.28-6L4L 17-18L
U10 0.0 1.80 3.28-6l4l 1718L
U16 0.0 2.49 5.08-6I1L 17-25L
U18 0.24 1.5 3.28-AMC1117 F0631J
DU2 0.0 3.28 5.05-6LKL-17-33L
DU3 0.0 2.51 5.05-6I1L 17-25J
DU4 0.0 1.24 3.28-AMC1117 F0631J
My model does have the U33 regulator but it does not have the 1 fat pin over 3 pins.
Hopefully someone can help me out and tell me what ones are bad or suspect and guide me to the right parts. Thanks

[budm]

Re: Vizio GV42L

"U5 4.3 1.23 3.29-AMC1117 F0631J" This is bad.
If the adjust pin 1 has 4.3v, then the output pin 2 should have 4.3v +1.25v = 5.55v which will be an odd ball voltage.
Please recheck the reading.
The voltage between the pin1 ADJ pin and the Output pin should always be 1.25V. The output voltage (pin 2 and Ground) = 1.25 + the voltage reading on the Adj pin (ref. to Ground)

[Nick4208]

Re: Vizio GV42L

I rechecked U5 it is .43 1.23 3.28 Do you still think its bad? What about U18 do you think that one is bad also?

[budm]

Re: Vizio GV42L

"U18 0.24 1.5 3.28-AMC1117 F0631J" 1.25 + 0.24 = 1.49V, within 2%, OK.

"U5 it is .43 1.23 3.28" 1.25 +.43 = 1.66V, you are getting 1.23V, so it is bad.

[Nick4208]

Re: Vizio GV42L

Ok thanks I will order the part and update you with what I find out