Sharp LC-42SB48UT-a no standby voltage
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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: Sharp LC-42SB48UT-a no standby voltage
...I think you mean to set dmm on acv, and put - probe to - pin...then check the 2 ac pins with the + probe?Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
You have two inner legs (2) of the bridge rectifier, we are measuring AC so it does not matter which color probes go to which inner pins, same way as you read your AC wall outlet as you indicated in post 1.Last edited by budm; 06-21-2016, 02:31 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: Sharp LC-42SB48UT-a no standby voltage
Ok. There is no reading change on either of the ac pins. I've set my DMM to ACV, and there are 2 levels ....500 and 200v.Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
I haven't yet added solder to the bridge rectifier's pin ends, just fyi.Comment
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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: Sharp LC-42SB48UT-a no standby voltage
BTW, what is the history of this TV? Someone worked on it before you?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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Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
So do you get 120VAC between the two inner legs of the bridge now after you solder the legs?
I wonder if the person unsolder the legs trying to locate shorts.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: Sharp LC-42SB48UT-a no standby voltage
Please bear with me, BUDM, I'm wanting to make sure I do this right....for the bridge ac test, plug tv into outlet, then I use acv setting on my dmm and I just touch either probe to the inner pins, one at a time, to test them? New info...the standby is now reading 4.04v(after me re-soldering a diode and adding solder back to the bridge rectifier's 4 pins).Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
...and the filter cap now reads 165v, with tv plugged in, but not switched on. Tv won't switch on.Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
So you now have 4.04Vdc STBY? Not 5V?
Disconnect the cable between the power supply and the main board to see if you will get 5VDC.Attached FilesLast edited by budm; 06-22-2016, 11:13 AM.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: Sharp LC-42SB48UT-a no standby voltage
Bridge rectifier reads 521 and 514 on the 2 ac pins. I set dmm to diode mode, tv not plugged in.Comment
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Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
Well, then more digging to do to find out why you are only getting 4.04VDC instead of 5VDC.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: Sharp LC-42SB48UT-a no standby voltage
Yeah, back to square one, I guess. Never had this happen, in the several I've fixed. Hate it...I'm working on a few different sets that I'd hoped to get going for a school that needs them. Can you point me as to where to start, by any chance???Comment
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Re: Sharp LC-42SB48UT-a no standby voltage
May also be worth installing a new battery in your meter incase its giving false readings and may be worth checking a brand new battery with your multi meter and seeing what voltage its reading just incase your meters under reading etcComment
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Re: Sharp LC-42SB48UT-a no standby voltage
+1Never 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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