Pinebook pro Hardware failure: how should I diagnose it?

[alxndr.psclt]

Hello,
i'm a software guy, fairly inexperienced in hardware.
I love my pinebook pro, but it stopped working completely: no charging, no led, no startup (sd card, usb or internal). I would buy a new motherboard but it's out of stock; so I would want to try to repair it.
How should I start to diagnose it? I have no idea what failed. I've done some uboot updates, but I'm almost positive this is not my current problem (as the laptop was working for a few weeks since the updates).

Is there a begginer friendly guide for laptop repair that you would recommend? I have acces to basic tools at some hackerspaces around me.

Sorry for the large question; but I would love to get my PBpro back, because it's such a great machine I can't imagine any replacement. And I would love to use this opportunity to expand my DIY skills; I've already learned so much low level stuff by tinkering on the PBpro and Pinephone; why not get into hardware?

Thanks for any info, any pointer, any input.

Alex

[KC9UDX]

Are you sure it doesn't turn on? If it crashes and locks up before the power LED gets turned on, you might not know that it is turned on.

If you hold the power button for twenty seconds, you can be sure that it's actually turned off, not just locked up with no power LED. A serial console can help you diagnose a "dead" startup.

If the battery has been depleted, it's been widely reported that charging by USB-C is the only way to recover.

[kqlnut]

As for a guide for laptop repairs: I've really enjoyed watching some videos from Adamant IT. As a beginner I found it all very nicely explained in a pragmatic way, no fuzz around it.

[wdt]

There are 2 separate and distinct "long presses" (of the power button)
7-8 s is hard power off (always try this 1st)
20+ s is hard reset (for a mismatched uboot, remove the "bad" uboot)
Be aware that this arm device is not at all like x86 devices,,
the uboot is like a limited and specific bios, specific to the the particular arm family
It also has to mostly match the OS, some uboots are not very universal
A serial connection is the best way to see what is happening

[alxndr.psclt]

Ok; thanks for the infos, the battery is probably depleted now, I will try charging it via USB-C. It seems to me though that no charging is happening at all; but I will test that properly again. Mainly because I've tried to power it on without the battery (with the bypass cable connected), and still nothing. (almost 100% sure that I never plugged the battery AND the bypass cable....)

Then I'll try to boot it every way I know. If I still get nothing I'll try the serial console.
Thanks for the pointers, I'll keep you updates on my progress.
'Thanks for the channel recommendation, i'll check it.
Finally I have some basic Uboot knowlege, and I don't think that's the problem right now; but I'll know for sure when I see the serial output; if any,

---

Ok guys, thank you all for your input. I feel reeeeaaaallly stupid right now!!! (but also very happy)

I haven't used my PBP for a few months, believing it was broken. I would have bought a new one it was in stock. And all this time, the only problem was the empty battery. ? ^^

The USB-C charging did the trick. I remember having tried it at the time; but I guess the charger I used might have been to weak! Or the cable broken. Or maybe I was just not patient enough.


THANKS SO MUCH!

[KC9UDX]

Good to hear. I'm not sure what causes this (haven't looked into it) but I've even had it happen (with no time to investigate why). Under normal circumstances the battery shouldn't get that low. But when it does, this seems to be the solution.