SOURCE: No Picture
I replaced about 10 electrolytic capacitors and a PWM controller IC (MC34067P). Fortunately, i found an almost identical schematic diagram in the internet, so i started troubleshooting. To make it short, i replaced most of the electrolytic caps and mylar caps in the Preconditioner stage and VsVa Power supply stage. And finally the PWM Oscillator IC (MC34067P). You have to make sure that the Preconditioner stage is running ok, with an output of 380 to 395 volts DC. There are two fuses on the board (in my 32FD9954), one is for the mains AC located near the mains connector coming from RF filter (two wire connector- large wires), the other fuse is in the middle of the board. You measure the DC voltage on this fuse on the middle of the board and it should be about 380volts or above. The real culprit is the PWM IC. Initially i replaced the MOSFET (STY34NB50F) in the Preconditioner, then the caps, then finally the IC. Then it worked!!! I put back the old MOSFET, it's not damaged, so now i have a spare one. Just replace the electrolytics near the PWM IC (2.2u, 4.7u, 100u, 1000u) I think the design problem is that the IC is nearly located to the heatsink which generates lots of heat. The IC deteriorated in time and the electrolytes in the capacitor evaporated due to the excessive heat inside the case. I'm thinking of incorporating 120cm computer fans at the back to suck down the heat. Happy troubleshooting. I have the necessary diagrams if you need it. regards, Valerio
SOURCE: Power Led Flashing red 6 times....
the thermocoupler fuse is what it is called by the way. i also saw that it could be the "power board" which could or could not be synonymous with the thermocoupler. anyway, again it is a common problem with these models. Scott Jackson, MS
SOURCE: No power
It sounds like the backlight or an inverter board on the television may have failed. Check your warranty status on the television to see if you can get it repaired by the manufacturer for free.
SOURCE: power button is green - no blinks / no picture / no sound
Unplug it from the wall, wait 2 minutes and plug it back in. if problem still exists, its probably the main pcb.
SOURCE: My magnavox 37mf321d 37 LCD tv
This is a bad power supply and an easy fix. Their are several electrolytic capacitors on the power supply. If one is bad it will have a bulge on the top. Mine had a bad 2200uF and a bad 1200uF capacitor. About $7 worth of parts at Radio Shack. Radio Shack had the 2200uF but it was axial leads instead of radial. (leads come out of each end instead of one end) but It will still fit. They only had a 1000uf capacitor so I combined that with a 220uF capacitor and wired them in parallel. Make sure you put them in with the correct polarity.
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