Hello guys this will be my first post so plz be gentle lol. im working on amagnavox 42mf439b/f7 the issue is it powers on i get a solid green light and then the standby light flashs once every 15 to 30 secs ive tryed checking the screen with a flashlight as no backlighting comes on but no dice. ive checked all the caps and to the eye no bulging or bad caps. the set is unresponsive to the power button will only shut down if i ulplug the main board or the cba board. ive replaced the digital main board just out the go since it was pretty cheap. next thoughts were t con or inverter board ? im somewhat dmm friendly and can solder so fire away any help appreciated!
42" Magnavox trouble
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Re: 42" Magnavox trouble
maybe check the fuse on the tcon board, the label will start with an F for fuse. -
Re: 42" Magnavox trouble
careful when working with the power supply board, HIGH VOLTAGE on primary side.Comment
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Re: 42" Magnavox trouble
Well, start with this so we can see what we are dealing with.
https://www.badcaps.net/forum/showthread.php?t=39740
Also read this:
Basic LCD TV and Monitor troubleshooting guides.
The link is under my signature.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: 42" Magnavox trouble
thanks for taking the time budm and nomoresonys im very new to this have one repair tv wise under my belt but really enjoy working on electronics and learning from those who have more experience than me. most of my electronic back ground other than tvs is just building my own pc's.Comment
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Re: 42" Magnavox trouble
So you replaced the big brown board on the right?
This one of those FUNAI/SYLVANIA/EMERSON/PHILIPS/MAGANAVOX TV.
Is there a chassis number printed on the model number sticker?
For example:
42MF438BF7_LC8.14LA
"LC8.14LA" is the chassis number.Last edited by budm; 01-02-2015, 08:07 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: 42" Magnavox trouble
Yes both fuses on inverter board Check out at 24v and I get voltage at the caps on the inverter board but past the caps those transformer things lol dunno what there called there is no voltage. Both sets of connectors the red wires are all 24v.Comment
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Re: 42" Magnavox trouble
ok so budm this is the board that i replaced the digital main and then the sec picture is of the other connector on the inverter. all the red wires as i said read out 24v but the 4 blue wires voltage are all very low im not near the set to take the readings again but i will tonight .... and i will also try and get that model number you were asking for.Comment
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Re: 42" Magnavox trouble
I check fuses in diode mode, one probe on each end, if no reaction or stays ol, then its probably bad, if reading is close to 000 then its prob. good.Comment
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Re: 42" Magnavox trouble
maybe check expected voltages coming from power supply, a lot of them have legends by the connectors, that show expected voltages 3.3 ,5 ,12 ,24, etc.Comment
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Re: 42" Magnavox trouble
Found this on my search of the internet thought i would share it !!Attached FilesComment
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