Re: Sharp LC-C4655U Flashing OPC and Power lights.
Removing D9701 does result in 3v at PS_ON. The diode tests 0.60 one way and 0 the other.
Removing D9701 does result in 3v at PS_ON. The diode tests 0.60 one way and 0 the other.
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Last edited by berrmich; 08-26-2023, 03:33 PM. -
Re: Sharp LC-C4655U Flashing OPC and Power lights.
did the power supply turn on as well? If it did, check if there were any voltages on LB plug. If there are no voltages, try supplying 5v to stb on the inverter, you can use a 470~1k resistor if you like.Last edited by R_J; 08-26-2023, 05:11 PM.Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
Yes. When I hit the power button it did. Lots of clicking when I first plugged it in. After hitting the power button I had 12v and 60 but nothing at the LB plug.
I did not have to start with the chan/volComment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
I don't have a resistor. What's the best way to do this?Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
With STB 5v. Lights turn on but they turn off and back on every 10 secs or so. LB on inverter:
Pin1 - 0
Pin2 - 5v
Pin5 - 3v
Pin8 - 3vComment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
Pin 5 is the error pin so I suspect there is a problem on the inverter, if the LB is still connected to the main board it is likely telling the main board to shut downLast edited by R_J; 08-26-2023, 05:45 PM.Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
Ah. Hence the ERR label. So main board is probably fine? What types of things on the inverter can cause the error? And yes I kept the plugs in when I jumpered. Just shoved in the top.Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
The first thing I would check are the transformers, The transformer has two secondary's so check the resistance of each winding, they are usually around 1000Ω so check each transformer and see if one of the readings is not like the others.Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
I think I'm checking these right? didn't find a diagram in service manual. Look at picture to see if I'm doing right. If so I'm getting consistent readings on all of them.Attached FilesComment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
If I remember this should be the secondariesAttached FilesComment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
No that doesn't work. Here is the only thing I could find on the transformers.
2874026700 transformerAttached FilesComment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
The original way you checked the transformers is the correct way so I suspect they are ok. On these inverters, transformer failure is common, but so is having a bad ccfl in the panel, or even bad connections between the ccfl tubes and there sockets can cause a problem.Last edited by R_J; 08-30-2023, 04:02 PM.Comment
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Re: Sharp LC-C4655U Flashing OPC and Power lights.
Remove one of the transformers so you can see and check the windings, with it removed there will be nothing else effecting the readings, sometimes transformer pins are just used for mounting and are not connected to a winding.
If all the transformers checked the same I suspect they are all ok, 1.7k seems fine, if one was 1.5k or something like that I would suspect it was bad.
I suspect it is like this pictureAttached FilesLast edited by R_J; 09-01-2023, 08:40 PM.Comment
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Hi all!
I'm trying to troubleshoot a Microsoft Surface Pro (5th gen) model 1796 that won't power on. Motherboard model is M1007506-015. My priority is retrieving data, but the SSD is integrated so it looks like if I can't repair it it'll need to go to a data recovery company. I've done a little basic board repair before, but nothing this advanced until now. So please forgive my ignorance in advance. 😅
I found the boardview for this laptop in the forums here, and am able to open it on my PC with FlexBV.
https://www.badcaps.net/forum/troubl...-hardware-devi... -
As the Elitebooks (820, 840 all gens) only show flashing Power LED and flashing CapsLock (continuously) + a very soft "ticking" noise near the DC Jack,
I wonder if re-flashing the BIOS might be of any use here.
As far as I understood, steady flashing either means insufficient power or a CPU/GPU/Motherboard issue. I use the original 65watt power supply.
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Please correct me if i'm wrong but i understand the flash sequence indicates a possible power supply problem, can anyone say if this is accurate information? So going on that i went ahead and tried a factory reset, checked... -
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