Power brick short followed by HD errors

yuvadm · 2015-08-19 11:42:58

The power brick of my X200s just shorted yesterday, I saw smoke coming from the three-pin plug that connects the mains outlet to the brick and immediately disconnected it from the wall and the laptop.

Everything is still working but I can't help noticing my boot times are slightly longer now.

I'm also seeing this error occasionally in dmesg:

[   40.552803] ata1: exception Emask 0x40 SAct 0x0 SErr 0x40800 action 0x7
[   40.552809] ata1: SError: { HostInt CommWake }

Any idea what got fried? I'm still on battery power, should it be safe to reconnect the brick with a new cable, or should I dump it?

Last edited by yuvadm (2015-08-19 11:43:57)

mpan · 2015-08-19 11:57:48

Are you sure the shorting was in the plug or the cable itself? If yes, then it's safe to connect a new cable and most probably nothing got damaged.

I would say the error in dmesg is related to the fact that you're running on a battery and not to the accident. Maybe a disk is being put to sleep to save energy and some kernel bug manifests itself upon an attempt to access the drive.

yuvadm · 2015-08-19 12:22:52

The short happened on the plug as I mentioned, but IIUC this might also originate in the brick.

The dmesg error coming from battery is interesting, looks like I have no choice but to test carefully and see what happens. Thanks!

R00KIE · 2015-08-19 14:00:52

See https://ata.wiki.kernel.org/index.php/L … _expansion

ewaller · 2015-08-19 14:32:02

Most power bricks put out a single DC voltage, usually on the order of 20V. They use that fairly high voltage to keep the current down so they can use physically smaller cables and connectors. (80W for a laptop at 20V --> 4A). All of the voltages used inside the laptop are usually generated by a switching power supply because of their high efficiency. So, all of the 12V, 5V, 3.3V, 1.8V, 1.2V are all pretty independent of the 20V input. Also, most laptop switchers are tolerant of a fairly wide input voltage range and are well protected when the voltages go out of that range.

I would be very surprised if something happened at the line input that would end up frying one component running off the same 5V/3.3V/12V as the rest of the computer.

As to your brick. If you are going to test it, be careful. If you have a meter, you might check for shorts from line to common and from line to ground (earth) before reconnecting power. Being careful, find someplace non-flammable (like a concrete floor of a garage). Find a power strip that has a circuit breaker and an on-off switch. Turn that switch off, plug the strip into a wall, plug the supply into the strip, do not plug the supply into the computer, turn on the switch and check that the breaker does not immediately trip. Watch for smoke and power off using the switch at the first sign of trouble.

If you have a meter, check the voltage out of the supply.

Arch Linux

#1 2015-08-19 11:42:58

Power brick short followed by HD errors

#2 2015-08-19 11:57:48

Re: Power brick short followed by HD errors

#3 2015-08-19 12:22:52

Re: Power brick short followed by HD errors

#4 2015-08-19 14:00:52

Re: Power brick short followed by HD errors

#5 2015-08-19 14:32:02

Re: Power brick short followed by HD errors

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