Re: Dell 2007WFP Won't Power On
Hey guys, just thought I'd give you an update, I purchased another working usb board and reassembled all the boards onto the frame along with the LCD panel. I plugged it in but yet again it doesn't turn on. not even the orange led power light came one.
I took the LCD panel off, Upon doing so I felt the logic board and noticed that it was unusually warm.
I stripped all the boards off the frame and just left the logic board attached to the New USB board. I then plugged in the power cable, immediately the Genesis chip on the logic...
croket
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Last Activity: 12-27-2016, 11:22 PM
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Re: Dell 2007WFP Won't Power On
Well I think I ran out of luck, I removed FD7 and FD8 and they tested ok, (got very similar reading as the others) the pad for FD8 was showing fluctuating readings so I removed the neighboring cap (C60) hoping that would stop the flocculation but it didn't.
I then soldered everything back in and it was back to square one, Until.... I kept probing around with my meter leads and I guess I must have accidentally shorted out a solder joint with another because now I Lost my F19, I get 18v on one side and not the other. So now I got NO voltage...Leave a comment:
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Re: Dell 2007WFP Won't Power On
Hey Plainbill,
I tested all 8 diodes and here are my readings. With my DMM set to diode, I placed the black lead to the cathode side and the red lead to the anode, on all the diodes I'm showing 137 on my DMM. When I reverse the leads I get numbers climbing up in the hundreds then changes to a single 1, in other words 200s,400s,900s,1600s,1900, then 1.
They all do this with the exception of 2 of them, Fd7 & Fd8. With the leads reversed, the the numbers climb and stop at 1054 every time.
Don't know if I'm...Leave a comment:
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Re: Dell 2007WFP Won't Power On
Yes that's correct, I get 0v to the tabs, only voltage is on the 2 soldered legsLeave a comment:
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Re: Dell 2007WFP Won't Power On
Yes I did measure all 4 the j598s, I get 19v to both the legs on all them. The row of fuses stamped with "G" have no voltage getting to them.Leave a comment:
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Re: Dell 2007WFP Won't Power On
Ok so your logic board is getting the same voltage on the pins as mine without the big USB board attached, so its safe to say the problem is isolated to the USB board. I don't get the 5v at the 'G' row.
PlainBill, sounds like your on to something with the gates not opening.Leave a comment:
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Re: Dell 2007WFP Won't Power On
Alexanna, if you power up just the logic board (with out the usb board) which pins have voltage & what do they read?Leave a comment:
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Re: Dell 2007WFP Won't Power On
I've uploaded another picture detailing the leg voltage on U4, U3 also has the same voltage....Leave a comment:
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Re: Dell 2007WFP Won't Power On
On both U3 and U4, Pins 9 show 18v and pins 15 show 0v. The connector at the end of the board is for the actual USB ports (2 ports mounted on a small board with 4 small caps). That connector reads 0v on all 8 pins.Leave a comment:
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Re: Dell 2007WFP Won't Power On
Yes F19 gets 19v in and 19v out...Leave a comment:
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Re: Dell 2007WFP Won't Power On
[B]Retiredcaps [/B] I re-tested with the USB board disconnected but had the same results.
I've uploaded some additional pics, one shows the bottom side of the usb board indicating the pins getting voltage,(took the picture first then plugged the board in
) the other is the U2 chip. The 4 IC's with 19v are part# J598.
I'm trying to be as detailed as possible with pictures guys , but if its too much I'll tone it down. I figured pictures tell a thousand words!
Thanks for jumping in on this Plainbill and...Leave a comment:
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Re: Dell 2007WFP Won't Power On
I just traced the circuit on the board for those 2 wires (brown and Black) coming into the logic board that read 19v. They go directly to the connector that connect to the USB board.
they don't energize the logic board at all. I've tested several other components on the logic board they they all read 0v, the entire board has no voltage. The usb board however is a hole slew of components reading 19v.
This leads me to believe that there has to be another wire that energizes the logic board, however there isn't. take a look at...Leave a comment:
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Re: Dell 2007WFP Won't Power On
Just did it, I got 0v on all legs both chipsLeave a comment:
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Re: Dell 2007WFP Won't Power On
I re-tested U13 and U5. This time I placed the red probe from the DMM on the black wire coming into the board showing 19v, With the black probe I touched every leg on both chips and I get 19v on my DMM indicating all the legs are grounded.
The weird thing is when I try to tone it out (continuity beep) they don't all ring out. On U13 only the left legs rings out and on U5 the middle leg rings out. I"m using one of the screw holes rings on the board for ground.
Any thoughts?Leave a comment:
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Re: Dell 2007WFP Won't Power On
Shouldn't I get some kind of voltage on the "in" pin on either regulator even if they are bad?
Leave a comment:
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Re: Dell 2007WFP Won't Power On
No I'm not getting any voltage on any of the pins of the regulators (U13 and U5). I've got 19v on the 2 far right wires (brown & Black )at the connector above the regulators.Leave a comment:
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Re: Dell 2007WFP Won't Power On
[B]retiredcaps[/B], Thanks for the compliments on the pictures, I realize how critical it is when working on an item that you don't have in front of you. I"m a big fan of close up detailed pics.
I've checked the U13 and U5 components on my board and they read ok, not shorted. Also read the the 2 diodes (FD4) on the USB board and they too were not shorted (i also checked every diode of the same Part# number as FD4) .
And yes you're correct, 19V is what I'm getting.
[B]Rtech, [/B] I removed Schottky diode (D701) to...Leave a comment:
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Re: Dell 2007WFP Won't Power On
Hello All,
I realize this post has been quiet for about 10 months now and I hope some one out there can still help me out.
I"m having a problem with my monitor, came home from work one day, try to turn the unit on but it didn't, I'm not even getting the pwr button LED light (orange or green)
I do have some electronics knowledge however not a pro.. I've taken it all apart and took some basic readings with my DMM. I've also posted some detailed pictures with my findings.
for starters I"m...Leave a comment:
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