Hi all-- I'm new here (and relatively new to electronics), and I'm working on repairing a Vizio E320i-A2 unit that powers on (with both the onboard controls as well as the remote) but stays locked up on the Vizio logo that displays onscreen. The LCD and backlight seem to be fine-- the logo is bright and crisp. The unit does not respond to any input (IR or onboard) once it is powered up.
So far:
- The voltages from the power supply check out fine.
- I've checked the voltage regulators on the mainboard and they all appear good. The LD1117 regulators output 1.2v and the GH16D outputs are 3.3v.
- I've also read a culprit could be the EEPROM, or in this case, the NAND flash chip. From what I understand there's no real way to check this. In any event, I measured 3.3v for the supply voltage.
Anything else I should be looking at or considering before I plunk down the cash for a new mainboard?
There are two ICs labeled "D9329" and I believe they are the BD9329. One is located near the power supply input and the LCD data output, and the other is located near the MT5112EE chip.
The first (by the PS input) measures as follows:
Pin 1: 9.67v
2: 12v
3: 5.1v
4: gnd
5: .9v
6: 1.68v
7: 11.81v
8: 2.67v
The second is slightly different:
Pin 1: 6.18v
2: 12v
3: 1.57v
4: gnd
5: .9v
6: 1.44v
7: 11.81v
8: 2.65v
I'm not going to pretend to understand exactly what these do other than step down voltage, but from looking at the datasheet and the voltages it seems they are consistent. The difference between pin 1 input is about the same as the difference on the pin 3 output.
You can see a photo of the board here.
Definitely appreciate any knowledge or suggestions-- it has been a good learning experience already, but it'd be even better if I could actually fix it instead of replacing the whole board
So far:
- The voltages from the power supply check out fine.
- I've checked the voltage regulators on the mainboard and they all appear good. The LD1117 regulators output 1.2v and the GH16D outputs are 3.3v.
- I've also read a culprit could be the EEPROM, or in this case, the NAND flash chip. From what I understand there's no real way to check this. In any event, I measured 3.3v for the supply voltage.
Anything else I should be looking at or considering before I plunk down the cash for a new mainboard?
There are two ICs labeled "D9329" and I believe they are the BD9329. One is located near the power supply input and the LCD data output, and the other is located near the MT5112EE chip.
The first (by the PS input) measures as follows:
Pin 1: 9.67v
2: 12v
3: 5.1v
4: gnd
5: .9v
6: 1.68v
7: 11.81v
8: 2.67v
The second is slightly different:
Pin 1: 6.18v
2: 12v
3: 1.57v
4: gnd
5: .9v
6: 1.44v
7: 11.81v
8: 2.65v
I'm not going to pretend to understand exactly what these do other than step down voltage, but from looking at the datasheet and the voltages it seems they are consistent. The difference between pin 1 input is about the same as the difference on the pin 3 output.
You can see a photo of the board here.
Definitely appreciate any knowledge or suggestions-- it has been a good learning experience already, but it'd be even better if I could actually fix it instead of replacing the whole board

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