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reessi · 08-20-2025, 01:47 PM

I've checked quite a few of the sequences, basically the blue ones without circles all work but reset every 15 seconds but lots of the blue with red circles all belonging to U7800 are not working..

POWER SEQUENCE:

U7650 BLUE Numbers:

1 -> PPBUS_G3H -> Looping 12.22v @ 30mah when resets Batt Dis-connecting? / 11.6v When charging @ 0.5 – 0.8a.
Just Batt -> 11.22v Stable.
Just Charger – 12.55v/12.22v Looping!
2 -> Power Button -> U7800 (Showing 3.3v) Then:
U7650 – Pin 12 -> 3.35v
21 En -> 1.98v
3 ->...

reessi · 08-20-2025, 05:23 AM

No I didn't have these, I was going to work through the Power Aliases page on the schematic.

Where did you get these?

Many Thanks.

reessi · 08-19-2025, 03:19 PM

I already did that on every inductor I could find, none are low except the CPU ones as expected.

I'll do some checking again but I spent quite some time looking for shorts so far..

What about the missing outputs on U7800?
Should they be on at this stage or come on later?

PVCCPCOREPRIM -> 0v (SW0 & SW1)
P1VPRIM -> 0v (SW0 & SW1)

I'm going to work through all the power rails one by one from the schematic and see if any are short..

reessi · 08-19-2025, 02:32 PM

Sorry actually the voltage is cycling quickly, 3.3v, 3v, 2.84v, something like that but probably too quick for my multimeter!

Same on both lines.

Diode readings if helpful:

SCL - 1300
SDA - 1255

OK just realised you said with charger only... On charger only the voltage is stable at 3.34v well occasionally changes to 3.32v but I don't think that is anything. It cycles with the battery connected.

reessi · 08-19-2025, 02:26 PM

Actually I already checked SCL and SDA earlier due to seeing that in another thread.. But checked again now:

1 -> 0v
2-> 3.3v
3-> 3.3v
4-> 0v

By the way nothing is in those lines when the fuse is removed. Also with the fuse removed the USB meter stays at 5v... Is this expected?

reessi · 08-19-2025, 10:39 AM

Hi mate,

Pin 1 shows 12.22v no changes after removal with battery connected and charger.

1.4v with just battery.

And 12.22v with charger no battery.

It is stable, 12mah consumption on the USB C meter in all cases.

Cheers.

reessi · 07-21-2025, 04:53 AM

Can anybody help please? I do not know where to go from here?

Many thanks.

reessi · 07-15-2025, 03:03 PM

UPDATE:

After reading online about the power sequences of various motherboards I found that after the power button (NBSWON1# into ITC) is pressed then ITC relays that signal to the PCH (DNBSWON#).

These signals happen as expected but then PCH is supposed to send SUSC# back to the ITC which in turn should turn on everything else with SYSON. But it does not send this signal!

SUSC# is not shorted (800 diode mode). So either the PCH is faulty or there is something the PCH is expecting first.

I experimented by injecting 1.8v on to SYSON and MAINON...

reessi · 07-02-2025, 12:36 AM

I didn't realise there was some more replies in here, I never solved it.. Could be bad PCH as reclaimed or not soldered properly.. I don't know and I don't want to keep buying PCH's in the hope one will work..

Very dis-appointing..

reessi · 06-03-2025, 03:14 PM

Panel Data Sheet......

reessi · 06-03-2025, 10:08 AM

Update - After being on over half an hour again the brightness difference has fixed itself! Any ideas why it happened and then fixed itself? Cheers

reessi · 05-16-2025, 07:03 AM

Ok I rebooted again and now it seams to be fixed.. Thanks for the input.. Maybe will help someone else with this board.

reessi · 05-16-2025, 07:02 AM

There was no mention of this being a fix in the bios revisions..

reessi · 05-16-2025, 07:02 AM

I updated the bios from F16 to the latest F22 and now it resumes but hangs on the login screen.. Sometimes after a few minutes it logs in and sometimes it turns black with the cursor still moving and never logs in..

Windows 11 is fully updated, as is the graphics driver..

I'll have a play around and update if can find the problem..

reessi · 05-15-2025, 03:38 PM

Yes I assumed it worked as the it goes to sleep when I close the lid and attempts to unsleep when opening (Flashing power light goes solid) but same result..

I double checked where it was though, it is on the sub board which I unscrewed to access the hall sensor (X32C) and used a magnet to also confirm.

One thing I found was some corrosion in the connector on the sub board.. But I cleaned it up and everything on the sub board appears to be working (Power button/Hall affect/USB's/Audio jack)...

I suppose it could have caused some damage on the main board if...

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