Following up as I just saw I never did. The issue on that motherboard was the PCH. Once I lifted the PCH, there were several traces that were ripped. As said, some aux circuits have to properly initialize and they weren't.
Replacing the PCH / traces should do the trick.
malogro
Member
Last Activity: 09-12-2024, 05:53 PM
Joined: 03-08-2023
Location: NM
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BIOS request for Asus ROG Zephyrus GU502LU
Could not find said sticker. Including photos from both SSD slots as well as a further away view.
Wait - is it this guy?
It would appear my S/N is L6NRKD006418245...Leave a comment:
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Re: Clean BIOS request for a GU502 LU
It is an Asus Zephyrus GU502 LU.
Sticker for the serial number is gone from the back cover. So unless there's another way to verify on the motherboard for instance, I have no idea what the S/N is.Leave a comment:
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Clean BIOS request for Asus ROG Zephyrus GU502LU
Hi all,
Background on this is that this laptop does not show RAMRST#. All other voltages present and looking OK. Only suspect now is BIOS, before declaring board fully dead due to CPU/PCH issue.
Attached please find the original BIOS dump. Any help is appreciated!
Thank you,...Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Just to update y'all:
After receiving the new parts and soldering the new PUB1, the board now works. It's possible for the previous unit I may have used too much heat or it just went wrong somehow in one soldered pin
In the interest of anyone who may google this and tries to diagnose problems, here's what the voltages look like for a PUB1 on this board with a fully charged battery plugged (pins in order starting at 1):
ACIN_CHG: 2.21V
AC_IN: 3.16V
...Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
ACOK 3.1V.
And Mr. Salad Fingers over here WAS measuring all the pins on PUB1 when he accidentally shorted two and PUB1 went out with a bang.
Will have to replace and remeasure (this time with real care) when the replacement unit comes in a few days. I'll post it then assuming I don't fumble again.
On the bright side, we'll be sure (or not) if it was the PUB1 all along.Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Will measure ACDET/ACOK/ACDRV and post.
Gate voltage for good board is ~19V. It is able to charge this same battery (and any other battery for that matter).Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Got it. For reference it measures the same as the MOSFET on my good reference board. Will remove later today and measure, can't access the hot air station now.Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Source to drain: ~200kohm
source to gate: 20kohm
drain to gate:> 1Mohm
edit: got confused on terminalsLeave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Source is at 15.3V, same as gateLeave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
CSON to CSOP directly on IC measures 2.4 Ohms, roughly the same as reference board.Leave a comment:
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Re: Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Posting this quick reply as it may be beneficial:
I have read and performed tests present in thread:
[url]https://www.badcaps.net/forum/showthread.php?t=90356[/url]
DC-in mosfets (the ones that were replaced):
All measure MOhms from source to drain and gate to source/drain.
Current sensing lines: The ones from DC-in measure 3.5 Ohms, same as reference working board.
DCIN: 19V
ACDET: Haven't measured, but assuming...Leave a comment:
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Acer Nitro 5 (EH5VF motherboard) all works except battery charging
Hi all,
Another puzzle if you are so inclined. Attached PCB/Schems.
Background:
This unit came to me as "no power". Simple visual inspection revealed a blown up PQB11. I replaced it along with PQB12 just out of standard procedure of replacing them as pairs, and even though it fought me tooth and nail I was able to get a new one in and the board booted fine first try after that.
I've since tested the laptop to boot and even stress tested; no issues whatsoever. However, battery won't charge. It will work off the battery no problems... -
Re: Acer Nitro 5 AN515-55-55M1 [GH51G mb] powers on, no vcc_core
Ah, ok, let me clarify. What I mentioned as VCC_GT is actually the graphics card core (NVVDD), so my bad there.
So VCCIN is missing, because something is not initializing correctly then. Is there any sort of checklist I can go through to see what is failing?Leave a comment:
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Re: Acer Nitro 5 AN515-55-55M1 [GH51G mb] powers on, no vcc_core
Update: BIOS was reflashed to ME clean. Same exact symptoms.
It DOES write to BIOS (I read back from it to see if it had changed), which I think is a good sign. But still no POST (CAPS LOCK test still negative).
My next idea would be to go for broke and replace PUZ1 or inject ~1.8V directly to VCC_CORE to see if any signs of life, but suggestions are appreciated....Leave a comment:
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Re: Acer NITRO 5 -AN515-57-536Q need a clean bios
Update: Placed bios back on board, still no boot, same symptoms.
I decided to read back the bios to see if anything was at least changed on it. It seems it has, which I'm assuming is expected due to the fist boot sequence.
I'll transfer back to the original thread. Seems BIOS is not the issue after all....Leave a comment:
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Re: Acer NITRO 5 -AN515-57-536Q need a clean bios
Interesting. Programming fails because of one address, 0x001FA000.
I think this means the BIOS chip is faulty. That would also explain the issues with the motherboard. I will try to get another chip and reprogram with the BIOS dump, now to hope no other corruption screwed up the dump, but I unfortunately think that's likely...
Edit: Erasing and rewriting seems to have fixed it. Let's hope it does....Last edited by malogro; 04-16-2023, 10:05 AM.Leave a comment:
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Re: Acer NITRO 5 -AN515-57-536Q need a clean bios
Much appreciated! Donation made as well. Will give a try tomorrow, fingers crossed.Last edited by malogro; 04-16-2023, 12:45 AM.Leave a comment:
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Re: Acer NITRO 5 -AN515-57-536Q need a clean bios
Ahem, thank you for the patience. I would say it won't happen again, but I know me and it probably will.
Aaaaanyhow, consolidating all info here to make it easier for anyone searching later on:
Model: AN515-57-56FC
Serial number: NHQBWAA004124023DB3400
SNID: 12400917934
Motherboard model: GH51G LA-L181P Rev 1A.
Bios attached....Leave a comment:
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Re: Acer NITRO 5 -AN515-57-536Q need a clean bios
I believe it's the one right next to it, which is also why I was confused I think.
It's an
XMC XM25QH128AHIGLeave a comment:
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