Hi everybody!
I've got a Vizio E65-F0 smart tv that is good and dead. It shows no signs of life when I press the power button on the back. The power LED in the lower right corner doesn't light, there is no backlight and no picture.
So I took the back off and started poking around figuring one or more of the caps had dried out. My esr meter says all the caps on the power supply board and the mainboard are less than 1 ohm.
I decided to check the voltages coming off the power supply they are as follows:
connector CN201
pin 1 (18vsb1) = 18v
2 (18vsb1) = 18v
3 (18vsb2) = 18v
4 (18vsb2) = 18v
5 (GND)
6 (GND)
7 (GND)
8 (GND)
9 (ps on/off) = 3.9v
10 (bl on/off) = 0v
11 (NC)
12 (NC)
CN301
1 (vsync) = 1.2v
2 (hsync) = 0v
3 (mosi)
4 (sclk)
5 (miso)
6 (cs)
7 (GND)
8 (fault) = 0v
9 (5v sw) = no connection
10 (GND)
CN601
1 (v out) = 36v
2 (vout) = 36v
3 (vout) = 36v
4 (nc)
5 (nc)
6 (nc)
7 (led 1) = 5v
8 (led 2) = 5v
9 (led 3) = 5v
10 (led 4) = 5v
11 (led 5) = 5v
12 (led 6) = 5v
13 (nc)
CN602
1 (v out) = 36v
2 (vout) = 36v
3 (vout) = 36v
4 (nc)
5 (led 7) = 5v
6 (led 8) = 5v
9 (led 9) = 5v
7 (led 10) = 5v
8 (led 11) = 5v
9 (led 12) = 5v
I take this these reading to mean (please correct me if I have it wrong) that the power supply is putting out the 18v standby power and the main board is telling the power supply through ps on/off to turn on.
However there are three things that jump out at me
1) The main board is telling the power supply to turn on but not the back light.
2) The voltage on the ps on/off pin is 3.9v I expected 3.3v or 5v so I'm suspicious of the 3.9v.
3) At least part of the main board is working if it's trying to turn on the power supply but not enough to actually work or light up the power led on the front of the TV.
The cpu does get warm when it's left plugged in a few minutes which to me means at least part of the cpu is active. But online reflowing the bga chips seems to fix all Vizio TV problems so I decided to reflow the cpu on the main board which is why you'll see flux on the board in the picture. Reflowing it didn't change anything.
One final thing I can hear one of the local switch mode power supplys on the main board whining softly. When I press any of the power, channel +/-, menu buttons on the back of the tv I hear the whining change pitch which makes me think the buttons are having some effect since the load on the local supply is changing.
What should I look at next or do you think the cpu is dead? Is 3.9v normal for the ps on/off signal on a Vizio TV?
I've got a Vizio E65-F0 smart tv that is good and dead. It shows no signs of life when I press the power button on the back. The power LED in the lower right corner doesn't light, there is no backlight and no picture.
So I took the back off and started poking around figuring one or more of the caps had dried out. My esr meter says all the caps on the power supply board and the mainboard are less than 1 ohm.
I decided to check the voltages coming off the power supply they are as follows:
connector CN201
pin 1 (18vsb1) = 18v
2 (18vsb1) = 18v
3 (18vsb2) = 18v
4 (18vsb2) = 18v
5 (GND)
6 (GND)
7 (GND)
8 (GND)
9 (ps on/off) = 3.9v
10 (bl on/off) = 0v
11 (NC)
12 (NC)
CN301
1 (vsync) = 1.2v
2 (hsync) = 0v
3 (mosi)
4 (sclk)
5 (miso)
6 (cs)
7 (GND)
8 (fault) = 0v
9 (5v sw) = no connection
10 (GND)
CN601
1 (v out) = 36v
2 (vout) = 36v
3 (vout) = 36v
4 (nc)
5 (nc)
6 (nc)
7 (led 1) = 5v
8 (led 2) = 5v
9 (led 3) = 5v
10 (led 4) = 5v
11 (led 5) = 5v
12 (led 6) = 5v
13 (nc)
CN602
1 (v out) = 36v
2 (vout) = 36v
3 (vout) = 36v
4 (nc)
5 (led 7) = 5v
6 (led 8) = 5v
9 (led 9) = 5v
7 (led 10) = 5v
8 (led 11) = 5v
9 (led 12) = 5v
I take this these reading to mean (please correct me if I have it wrong) that the power supply is putting out the 18v standby power and the main board is telling the power supply through ps on/off to turn on.
However there are three things that jump out at me
1) The main board is telling the power supply to turn on but not the back light.
2) The voltage on the ps on/off pin is 3.9v I expected 3.3v or 5v so I'm suspicious of the 3.9v.
3) At least part of the main board is working if it's trying to turn on the power supply but not enough to actually work or light up the power led on the front of the TV.
The cpu does get warm when it's left plugged in a few minutes which to me means at least part of the cpu is active. But online reflowing the bga chips seems to fix all Vizio TV problems so I decided to reflow the cpu on the main board which is why you'll see flux on the board in the picture. Reflowing it didn't change anything.
One final thing I can hear one of the local switch mode power supplys on the main board whining softly. When I press any of the power, channel +/-, menu buttons on the back of the tv I hear the whining change pitch which makes me think the buttons are having some effect since the load on the local supply is changing.
What should I look at next or do you think the cpu is dead? Is 3.9v normal for the ps on/off signal on a Vizio TV?
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