Oh I see... thank you very much for the info. I have determined I have no EDP_PANEL_PWR_EN coming from U0500
R0542 is fine. I am guessing U0500 is bad :/
bdawg
Member
Last Activity: Today, 10:29 PM
Joined: 10-28-2014
Location: Lawrenceville, GA
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Re: 820-01598 not booting but has power
Oh I see... thank you very much for the info. I have determined I have no EDP_PANEL_PWR_EN coming from U0500 R0542 is fine. I am guessing U0500 is bad :/
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820-01598 not booting but has power
Hello, any help with this is greatly appreciated as always. This board has power but is missing ppvccgt_cpu_ph1 and ph2. The board is taking 20v / 450ma but has no chime, no video. Fan spins and CPU and surrounding components heat up. Resistance on L7410 and L7420 both read 2.8 ohms. I don't have another one of these boards so I am unsure if that is normal. And basically 0v on those. All other rails seem fine. Any suggestions from here?
Thank you so much everyone
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Re: 820-01041 20v and cycling 50ma
Thank you so much for your reply and help.
Resistance is low only the coils around CPU and GFX VCCs. 10ohms and less. The rest are no where near that low.
PPBUS_G3H is very steady at 12.62V on both sides of F7000.
Voltages on requested points:
I2C_PWR_SDA- 1.8v
I2C_PWR_SCL- 1.8v
SMBUS_3V3_BATT_SDA- 3.3v
SMBUS_3V3_BATT_SCL- 3.3v
Haven't found any missing current sense resistors at this point. I will keep examining to see if something else shows itself...Leave a comment:
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820-01041 20v and cycling 50ma
Hi all, the A1990 board I have is taking 20v but cycling 50ma and I have hit a wall in troubleshooting. I can't find any shorts anywhere and I have tried configurator 2 with no luck on reviving it. The only area getting slightly warn is the T2 chip. Would that be what is bad or should I keep looking for a short somewhere. I have gone through all the rails. What circuit most likely is stopping the boot process at 50ma? Any help would be very much appreciated. Thank you! -
Re: Schematic for Mac mini late 2014 logic board
Just wondering why macbook schematics and boardviews are always available and no other mac machines are. Why is it only macbook ones are ever able to be leaked?Leave a comment:
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820-00165 MDM removal
Hello all... I was wondering if replacing the EFI chip can remove an MDM enrollment if the chip is programmed with a different serial number. Basically I want to program a serial from a junk board to it and install it to a board that currently has MDM locked to it. It is linked to the serial number is it not? Has anyone tried it and did it work or not? If it didn't work please tell me why. Thank you! -
Re: 820-3330 stuck on usbmultitouch driver
Have not tried Linux or Windows. I will post a photo of the screen later once I get home. Thank you very much!Leave a comment:
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820-3330 stuck on usbmultitouch driver
Will not load into macOS or ASD. When running verbose mode it always stops at usbmultitouch driver. Just stops there. I have scoped the board for missing parts and corrosion and all looked good. I have replaced u5701 and u2700 with no change. Both get necessary voltages to operate. What else do I look for at this point? Thank you! -
Re: 820-3330-B No image - No Backlight.
Hey there, I have the same board with the same issue and have a question about U8900. All of the correct voltages and enables are present for the chip but there is no output on pin 1 (pwrgood). I have replaced the chip and still same result. Any suggestions or direction on this matter would be greatly appreciated. Thank you!!Leave a comment:
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Re: A1466 SSD not recognised
Hello I am having a similar issue but it is weird. The internal ssd is recognized and is readable when booting from an external drive. But if trying to boot from internal it doesn't show up in the boot menu. Externals show up and boot. Internal shows nothing unless booted from another drive, then it shows up. Drive works in another machine with no issue. I am lost on this one. Help please and thank youLeave a comment:
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Re: xbox one-s
Hey all, I have an xbox one s that is shutting itself off right after I turn it on. Fan does not turn and so seems like a short. I have replaced all the mosfets that everyone talks about but still having the same issue. Since I cannot find a schematic I am lost on what to try next. Can anyone point me in a direction from here? I don't know what is connected to what and what values should be. Much appreciated!Leave a comment:
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Re: looking for schematics/boardview for Mac mini A1347 Late 2012
How are there no schematics or boardviews? Apple has to have these if they designed them. I am so curious how these are not available and the macbook stuff is all over the place. Why would they keep mac mini under lock down??Leave a comment:
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Re: New Members - please post your introductions here
Well ok, here I am. I'm Brian! I'm a PC repair technician for PC's and Macs. Basically just want to see what info I can scour from this forum
I'm actually looking for a schematic for Macbook Pro logic boards. Part # 820-2915-B at the moment. If anyone has one please post. Thank you very much!!
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