Pinebook Pro not powering on / not booting (tried things listed in wiki/forum)
Alright, some things you can try:
- Check the RK808-D SOC in the schematic and measure the PWRON pin. See if you see a voltage when you press/hold the power button. If you don't trace its path and check the components involved in that.
- On the same chip, check the pin CLK32KOUT1. It's supposed to be always-on, so see if you get a clock signal from that.
- Check VCC1 on the same chip to see if you at any point you get a voltage on it.
If you get the PWRON signal, but no CLK32KOUT1, the chip may be broken. You can also check BOOT0 to see if anything happens on that if you try to power the machine.
Some other things:
- Check the RK3399 chip. See if EFUSE_VQPS gives you 1.8V. If it doesn't I suspect it has been tripped - but I don't understand the exact mechanics of it.
- Also check V27 on this same chip to see if it gets a signal when you attempt to power on.
There's another fuse at the DC-058 DC-IN. Check the schematic. See if the R1206 fuse has any continuity. If it doesn't, you might be able to get off lucky by just replacing the fuse. I wouldn't recommend bridging it, as there might be a good reason (short-circuit) that the fuse tripped. It's supposed to be a fuse that resets itself, but sometimes it takes a long time for its resistance to reset back to workable levels.
If you still can't find it, but you suspect a short-circuit - there's another technique you could try: get a small squirt bottle of isopropyl alcohol (has to be pure). You can spray it on random areas of the board. If it fizzles due to heat, it's likely that you've found a short. Usually this will be a small component or chip, and you can then use the schematic to confirm the short-circuit. Replacing it could fix your issue.
Anyway, best of luck and let us know if you manage to fix it!
If you're lucky, you might have just fried the power board. Try and see if my suggestions will work.
- Check the RK808-D SOC in the schematic and measure the PWRON pin. See if you see a voltage when you press/hold the power button. If you don't trace its path and check the components involved in that.
- On the same chip, check the pin CLK32KOUT1. It's supposed to be always-on, so see if you get a clock signal from that.
- Check VCC1 on the same chip to see if you at any point you get a voltage on it.
If you get the PWRON signal, but no CLK32KOUT1, the chip may be broken. You can also check BOOT0 to see if anything happens on that if you try to power the machine.
Some other things:
- Check the RK3399 chip. See if EFUSE_VQPS gives you 1.8V. If it doesn't I suspect it has been tripped - but I don't understand the exact mechanics of it.
- Also check V27 on this same chip to see if it gets a signal when you attempt to power on.
There's another fuse at the DC-058 DC-IN. Check the schematic. See if the R1206 fuse has any continuity. If it doesn't, you might be able to get off lucky by just replacing the fuse. I wouldn't recommend bridging it, as there might be a good reason (short-circuit) that the fuse tripped. It's supposed to be a fuse that resets itself, but sometimes it takes a long time for its resistance to reset back to workable levels.
If you still can't find it, but you suspect a short-circuit - there's another technique you could try: get a small squirt bottle of isopropyl alcohol (has to be pure). You can spray it on random areas of the board. If it fizzles due to heat, it's likely that you've found a short. Usually this will be a small component or chip, and you can then use the schematic to confirm the short-circuit. Replacing it could fix your issue.
Anyway, best of luck and let us know if you manage to fix it!
(02-03-2020, 11:55 PM)aaspectre Wrote: I spilled my drink on my pinebook pro. I could not intervene as the reason it happened is because I passed out on it. It sat unintervened with for potentially hours.
It was spilled on from the right side, and upon disassembly I saw no evidence of liquid reaching the left side, yet I am experiencing identical symptoms to those of this post. My misfortune may be your clue.
If you're lucky, you might have just fried the power board. Try and see if my suggestions will work.
