[SOLVED] Thinkpad T460 not charging (power light blinking)

ayr0 · 2017-07-12 20:31:27

My laptop battery quit charging earlier this week. The battery is about 14 months old, and has been working splendidly until this week.

Symptoms:
1. When attaching to AC, power light blinks 3 times. This happens even when the machine is powered off and AC is connected.
2. acpitool -B shows the charging status is "Unknown" when attached to AC
3. When attached to AC, battery does not charge, and computer seems to run entirely off AC.

Things tried:
1. Charging when laptop is powered off doesn't seem to work
2. Charging during suspend seemed to work once, but not anymore.
3. Swapped batteries with a known good battery. Power light still blinks 3 times when attaching AC. used different charger too, same result. My laptop cannot charge the known good battery.
4. Upgraded BIOS to latest version.
5. Taking and reinserting the battery (waiting various amounts of time). I attempted to bleed any extra power my disabling the internal battery and holding the power button down for 10s.

Things I noticed:
1. There was a kernel/systemd update right before it quit charging. I downgraded kernel/systemd and any other acpi related package that I've updated recently. Downgrading all of these didn't seem to change anything.
2. Installed linux-mainline 4.12, no luck either
3. uninstalled /reinstalled tpacpi-bat. No improvement.

The blinking power light leads me to believe it might possibly be related to hardware (though, I was really hoping it is software related). I couldn't really find any issues that matched my situations exactly (most were missing the power light blinking symptom). The closer related subjects (that suggested really nice ideas) but didn't seem to solve my problem.
1. https://bbs.archlinux.org/viewtopic.php?id=152860
2. https://bbs.archlinux.org/viewtopic.php?id=157598

The next thing I want to try is booting up a ubuntu livecd and seeing that helps.

Has anyone experienced an issue like this with their thinkpad? Any guidance on this would be helpful. I'm trying to pin it down to either software or hardware. I'm really hoping that I don't have to replace a motherboard or something. Is anyone familiar with the charging circuitry on newer Thinkpads?

Last edited by ayr0 (2017-07-21 04:04:19)

epicepee · 2017-07-17 22:28:03

The blinking when you plug in AC is standard on ThinkPads since at least the XX40 series.

Definitely try Ubuntu. Also try Windows if you can -- this might be the ThinkPad's battery manager acting up.

Also of interest is tpacpi-bat which can control charging. Check states?

Blasphemist · 2017-07-18 00:23:47

My toshiba satellite is considerably older than your thinkpad is from your description but when the battery all but failed the power led began to blink constantly. In my case it's just a bad battery.

ayr0 · 2017-07-18 16:18:02

@epicepee, I guess I just haven't noticed the blinking power light on AC before. Hopefully it's a red herring. I don't have windows, so I can't really try that. How does Thinkpad's battery manager work?

@Blasphemist: I'm pretty confident that the battery is still good.

A bit of an update: I attended a conference this past week and was able to meet up with a fellow Thinkpad owner. We swapped batteries and chargers and were able to rule out a bad AC adapter and a bad battery. I couldn't charge my battery nor his battery with either mine or his adapter.
I tried a ubuntu on a live usb and still was not able to charge the battery.

I opened up the laptop and didn't see anything suspect. I was looking for any signs of a bad component.

I do have tpacpi-bat installed, but I've tried it disabled and no luck. I've also tried disabling tlp.

I think I'm going to let the battery discharge (but not completely) and maybe that might reset something. The next step after that is probably call lenovo (shudder).

R00KIE · 2017-07-18 17:05:14

ayr0 wrote:

I think I'm going to let the battery discharge (but not completely) and maybe that might reset something. The next step after that is probably call lenovo (shudder).

Careful with that, for my E560 lenovo corrected one bug when the firmware would let the battery discharge too much and after that the battery would not charge.

Regarding the blinking it is normal as others have said, but to be sure check the manual. That said if I had to guess I'd say that is either the battery manager acting up or a hardware problem, specifically the charge circuit on the laptop itself.

I've never changed the battery charge/discharge thresholds but you should check carefully if the problem is not an incorrectly set limit.

ayr0 · 2017-07-18 23:19:36

@R00KIE: The hardware maintainence manual procedure directs that the battery be drained to less than 50%. I'll try that and I'll do an audit of my charge/discharge levels and post any findings. Thanks for sharing your experience.

I'm still _really_ hoping it's not a hardware problem. (fingers-crossed).

ayr0 · 2017-07-21 04:03:59

Thanks @R00KIE and all the others that suggested checking thresholds. I checked charging thresholds again, and discovered that indeed there were conflicting charge thresholds. Anyway, I reconfigured the battery charge thresholds, and behold, they battery started charging!!!!!

Feel really dumb now, but I'm glad I don't have to call tech support. Thanks again everyone.

Arch Linux

#1 2017-07-12 20:31:27

[SOLVED] Thinkpad T460 not charging (power light blinking)

#2 2017-07-17 22:28:03

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

#3 2017-07-18 00:23:47

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

#4 2017-07-18 16:18:02

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

#5 2017-07-18 17:05:14

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

#6 2017-07-18 23:19:36

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

#7 2017-07-21 04:03:59

Re: [SOLVED] Thinkpad T460 not charging (power light blinking)

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