battery not charging; reads 28%, yet cannot sustain w/o cord

Lenovo Thinkpad t500 laptop computer wi...
February 9, 2013 at 11:25:01
Specs: Windows 8 Enterprise 64-bit (6.2, Build 9200), Intel(R) Core(TM)2 Duo CPU T9400 @ 2.53GHz (2 CPUs), ~2.5GHz / 6144 MB
When I hover my mouse over the power icon in the taskbar, I perpetually receive "28% available (plugged in, not charging)". Yet, as soon as I disconnect the power cord (with battery still attached), my laptop powers off. Under my monitor, the battery button keeps flashing orange.

I'm running Windows 8 on a Lenovo T500. My low battery levels are set to 15% and my critical levels to 7%.

This problem arose out of the blue. It was just sitting on my desk on battery power and then suddenly powered off.

Lastly, this may not be related, but when I first took a look at my battery to figure out why it suddenly powered down, the laptop was unusually hot, something I've never noticed before. I'd just dusted my peripherals recently too.

Help please?

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UPDATE

When I run my laptop w/o the battery in (cord only), I still get the same readings on the taskbar's power gauge, "28% available (plugged in, not charging)".

This leads me to believe that there is a problem that would not be resolved if I simply bought a new battery.


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#1
February 9, 2013 at 11:35:14
It's time for a new battery. The "battery gauge" is an approximation. Once the cells start failing to take a charge it's anyones guess. The bad battery can also overheat while you try to charge it.

They do not last forever and should be easy to find for your T500.


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#2
February 9, 2013 at 12:26:55
bump; updated original post

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#3
February 9, 2013 at 13:17:41
It sounds like it's not a battery issue. Start by updating system bios, all OS drivers and power management firmware. Also use contact cleaner on the battery-MB interface.

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Related Solutions

#4
February 9, 2013 at 13:54:15
To my mind we have not taken the battery or charger out of the equation yet.

Be very careful with updating BIOS. If you get it wrong you will need a new computer (motherboard at least). If the charging has been OK in the past I find it hard to understand why you suddenly need a BIOS update - they are rarely needed. If there is an update that mentions this particular issue then fine, otherwise I wouldn't go there.

Always pop back and let us know the outcome - thanks


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#5
February 9, 2013 at 14:27:41
Yes, thank you. The BIOS update is not without risk. But I have seen many cases of amazing improvement in system performance by updating the BIOS.

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#6
February 9, 2013 at 14:30:32
Re #5

"I have seen many cases of amazing improvement in system performance by updating the BIOS"

OK thanks - have noted your findings on this.

Always pop back and let us know the outcome - thanks


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#7
February 9, 2013 at 16:02:17
Thanks for the help thus far.

So I went into the device manager and updated every driver I could. I also went to a lenovo website and downloaded/installed some more drivers. Battery-MB connection has been thoroughly air-dusted. The same problems persist.

However, I don't know how to update power management firmware or the system BIOS (I'm willing to give it a shot).

Could I get more specific help in these areas please?


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#8
February 9, 2013 at 17:13:47
I don't know what is causing this but it's hard to imagine that "out of the blue" either power management firmware or BIOS suddenly needs updating. These are not like software updates, they both flash the actual chips (electrically) to do so - nothing in Windows could possibly have caused such a condition.

I'll therefore leave you with Paul1149 (or others) on this. Hope it does the trick and I'll pop back and eat humble if it does. I guess a buggy flash version is "possible".
http://en.wikipedia.org/wiki/Firmware

Always pop back and let us know the outcome - thanks


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#9
February 9, 2013 at 17:27:26
There are no guarantees with the bios flash, but I have seen corrupted bios that affected machines - to the point that I was on the verge of losing the machine. When I got the bios refreshed, problems instantly disappeared.

If you want to try it, I found the best way is to use the Windows-based utilities which you will find on the lenovo site. Follow instruction carefully - machine plugged in, preferably on a UPS since there is no battery backup. No progs running. Say a prayer and hit the button.

I don't know if lenovo uses its own power management scheme. If so it would be available near the drivers. There should be a firmware section.

I was sure this was a battery problem - I had the identical problem two weeks ago and had to replace the battery - until I saw that the misreading persisted even in the absence of the battery.

Here's another thing you can do. Fire up a linux boot disk such as parted magic or maybe puppy (not sure) and see what it says about the battery. That will get around the windows drivers/firmware, but it won't bypass the bios.


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