My Vizio Vw42L HDTV10A Turns on with the power button, the light changes from amber to white and the back light comes on, but there is no sound or video.
Went through all the Vizio posts for repair info.
Checked all the DC-DC converter voltages and the power supply input on the main board.
Fuses on main board, power supply and each fuse on inverter boards are good.
All measurements from circuit board ground.
Replaced u7, u8, u9 and u33
Replaced all the caps in the regulator section, I am waiting for some
parts to build a ESR meter so it was easier to just replace the caps.
Went through the flow chart in the service manual and think I found a problem at R20 it had 5 volts with no power and 0 volts with the power on.
manual calls it OPWRSB I have no idea what it stands for ?
Voltage at the regulators are
pin 1 2 3
u7 off 0 0 0
on .04 1.52 4.03
u8 off 2 3.29 5.13
on 2.05 3.29 5.08
u9 off 0 0 0
on 0 1.25 4.03
u33 off 0 0 .5
on 2.72 4.03 5.04
I need help with this, I just can't seem to track down
the problem with out having the Main Board Circuit Diagram.
Thanks for any help you can give me with this.
Went through all the Vizio posts for repair info.
Checked all the DC-DC converter voltages and the power supply input on the main board.
Fuses on main board, power supply and each fuse on inverter boards are good.
All measurements from circuit board ground.
Replaced u7, u8, u9 and u33
Replaced all the caps in the regulator section, I am waiting for some
parts to build a ESR meter so it was easier to just replace the caps.
Went through the flow chart in the service manual and think I found a problem at R20 it had 5 volts with no power and 0 volts with the power on.
manual calls it OPWRSB I have no idea what it stands for ?
Voltage at the regulators are
pin 1 2 3
u7 off 0 0 0
on .04 1.52 4.03
u8 off 2 3.29 5.13
on 2.05 3.29 5.08
u9 off 0 0 0
on 0 1.25 4.03
u33 off 0 0 .5
on 2.72 4.03 5.04
I need help with this, I just can't seem to track down
the problem with out having the Main Board Circuit Diagram.
Thanks for any help you can give me with this.
Comment