Lenovo laptop died!? Any ideas? Answered
I've got a "Lenovo Flex 2-15 Laptop" that recently just randomly shut down and died as if the battery and power was disconnected. I think this might have been caused by a faulty USB device drawing too much current. (specifically, a arduino-based gimbaled motor controller for camera stabilization on my quadcopter) When it was plugged in, the second I clicked to 'connect' to it via a GUI software interface for it, my computer instantly shut down. Since then it shows no signs of life. Any ideas what could have happened and why it does not boot?
It appears to still be under warranty so I'll see what I can do. I really hope that bad things didn't happen. My gimbal still works, but I guess a glitch in the software on the gimbal caused a transient voltage spike or overload on the USB port and either tripped some sort of safety protection or even worse, the mobo failed. Maybe the 5V regulator in the laptop and the one in the gimbal didn't agree with eachother and got into a bit of a voltage war!?!?!? IDK. I have a sneaking suspicion that it is a faulty polyfuse between the battery and MoBo that's failed.
The gimbal has a simple 5V 78m05 SMD regulator between the 12V lipo and 5V logic stuff. However the USB and 5V regulator share the same common connection. I think if something really bad happened, like the voltage regulator failing and dumping 12V into the USB port even for a short time, then I would expect the magic smoke to have escaped from the gimbal and the computer. From my experience, common AVR microcontrollers tend to fail pretty spectacularly with 12V. Since the gimbal still works, I am pretty confident that a low impedance 12V transient had not occurred. I think maybe the gimbal took too big a gulp of current and set off some sort of USB overcurrent protection. But I cannot open the thing, damn modern laptops don't even have removable batteries anymore GRRR! I'll file a warranty claim and see what happens, but does anyone have a better idea what could have gone wrong?