I have a Vizio VO370M 37" LCD TV that will turn on to the Vizio logo,have sound,but the backlights only light up on the sides for a couple of seconds then go out.The middle part of the screen doesn't fully light up.If you shine a light on the screen,you can see the picture.The Vizio logo is white.This happened during a storm.
I changed one capacitor on the power board that was out of spec,and when I went to try the TV,I lifted the edge where the stand goes to see if I had a picture,and there was no power.The main fuse was bad.I replaced it,and it went again.I found a shorted MOSFET on the power supply.After replacing that,I am now back to where I started.
I have tested the capacitors,transistors,transformers,and diodes in the power supply,and they all seem alright
.
Can a capacitor measure low ESR,and be low in capacitance?
One diode on the power supply measures shorted on the board,nothing off the board,but the spot on the board measures shorted.
Maybe a bulb shorting out on the frame?
I saw online how you can test the inverters with a cfl bulb.Will a bulb/bulbs from a 17" LCD monitor work,or are they too small,and will burn out?If the bulbs do light up,won't they make me think the power supply is good,when it's not,because the TV's larger bulbs draw more current,and this is causing the lights to not to fully light up because the power supply is not providing enough power?I saw a picture online of backlights not fully lighting up because of not enough power.
Any help is greatly appreciated.Thank You very much!
Tyler
I changed one capacitor on the power board that was out of spec,and when I went to try the TV,I lifted the edge where the stand goes to see if I had a picture,and there was no power.The main fuse was bad.I replaced it,and it went again.I found a shorted MOSFET on the power supply.After replacing that,I am now back to where I started.
I have tested the capacitors,transistors,transformers,and diodes in the power supply,and they all seem alright
.
Can a capacitor measure low ESR,and be low in capacitance?
One diode on the power supply measures shorted on the board,nothing off the board,but the spot on the board measures shorted.
Maybe a bulb shorting out on the frame?
I saw online how you can test the inverters with a cfl bulb.Will a bulb/bulbs from a 17" LCD monitor work,or are they too small,and will burn out?If the bulbs do light up,won't they make me think the power supply is good,when it's not,because the TV's larger bulbs draw more current,and this is causing the lights to not to fully light up because the power supply is not providing enough power?I saw a picture online of backlights not fully lighting up because of not enough power.
Any help is greatly appreciated.Thank You very much!
Tyler
