- Dec 1, 2013
Ugh legendary thinkpad reliability, my x230 decided to start losing power randomly while on battery.
1. doesn't happen on AC so it's not a solder point failure on something hyper critical...maybe.
2. it might not be heat related as CPU temps are fine, and it doesn't shut down on AC stress test
3. not software related cuz it dies in the BIOS
4. not mechanical as banging the machine around has no effect
5. working on AC so it rules out any power rail not generated directly by both the battery and DC in
6. state of charge doesn't affect the behaviour, so it may rule out the two or three switching FETs from battery to the main VINT20 rail in case they're a bit more droopy than usual
7. first place to investigate is scoping the main VINT20 rail and the battery input to see if it is the battery or not, and checking the control circuitry for said FETs
8. what am I doing with my life this isn't a macbook I'll just order a working donor unit for $50
Ahh sweet baby Jesus I hate intermittent faults, just die already so I can troubleshoot easier.
Awwh just as I was about to post this, I got a call from the nice chap who sold the unit to me and he's sending another unit for spares for just the postage cost. The guy sounded really sorry and sympathetic, I probably should have mentioned I'm a bit of an electronics hobbyist specialising in repair...
Losing power randomly sounds like a battery related issue to me. It might not be able to maintain a stable operating voltage. This usually happens with batteries that hold <80% of their design capacity.
I'm currently also encountering strange power-related issues on an 8 year-old HP Pavilion DV6 laptop. The backlight flickers while on battery power but doesn't flicker when connected to AC. I wanted to try and swap the LCD, but as it turns out it uses a CCFL backlight and all my new LCDs are LED backlit. I'm guessing it's inverter/lamp related so may as well do another CCFL to LED conversion.