Toshiba P55W Battery peekaboo

[swofra]

Hello all,
Toshiba P55W-C5314 with a PA5208U-1BRS battery. Worked fine for months until a couple of weeks ago. Laptop will not turn on using battery power. However, powers on fine with AC power. Battery shows 100% charged via battery icon displayed in the bottom right corner and also by running BatteryReport so it seems to be recognized in some way - yet the battery charge status light on the case does not illuminate so maybe it doesn't?

I've tried the uninstall battery method and it didn't work. Neither did leaving it plugged in to trickle charge. I tested the power at the battery connection point on the motherboard. With battery attached but AC adaptor not plugged in, I only got one reading: pin 7 at 3VDC. With the AC adaptor plugged in and the battery attached I got readings on pins 3 and 4 of 2.7VDC, pin 5 at 0.4, pin 7 at 3 and pins 8 & 9 at 0.7VDC. Worried that its a mobo problem vice a battery problem but looking for any suggestions. The battery is labeled 10.8V so if I'm measuring correctly at the right spot (see pic) and in the right manner (black probe touching metal, touch red to each pin to get the reading) it doesn't seem to get close to that.
Thanks in advance!

[stingerchamp]

Re: Toshiba P55W Battery peekaboo

Voltage on pin 6 which is SDA=?
Pin 7 is SCL 3v seems ok

[SMDFlea]

Re: Toshiba P55W Battery peekaboo

If thats the original battery its 5-6 years old. Install batterymon software, click on the small battery icon and post a screenshot like the one attached

[swofra]

Re: Toshiba P55W Battery peekaboo

Thanks for the responses. I am back from vacation.
To answer questions thus far:
Pin 6 I wasn't able to get detect any DCV using the procedures and counting pin positions described in my original post

Attached is the BatteryMon. I can't get a reading on battery power as the laptop immediately shuts off as soon as the AC plug is pulled.

Thanks!

[swofra]

Re: Toshiba P55W Battery peekaboo

What voltage should normally be going to the battery (when charging it) and is it on a typical/standardized numbered pin 9 (e.g. the 1st, 4th, etc)? Does the lack of readings on a particular pin indicate it could be a ground pin?
Lastly, I imagine that the battery wouldn't discharge the 10.8v unless the laptop was drawing it...but in my checks with the multimeter I never got close to 10.8. If I removed the battery from the laptop, the connector for the battery was too small to fit the probe - haven't tried with a thin wire yet unless that could yield some important diagnostic information.
Thanks in advance!

[piernov]

Re: Toshiba P55W Battery peekaboo

Not sure what you are trying to do… when you have a dead battery you replace the battery, no point in messing with the software or hardware.

[swofra]

Re: Toshiba P55W Battery peekaboo

Not sure what you are trying to do… when you have a dead battery you replace the battery, no point in messing with the software or hardware.

BatteryMon and another battery analysis tool shows that the battery is still at ~75% of its design capacity and 100% charged, that is why I want to make sure its not something on the mobo before I shell out the money for a new battery.

[SMDFlea]

Re: Toshiba P55W Battery peekaboo

BatteryMon is reporting a wierd number of charge cycles.Test all the mosfets around the battery connector area.

[swofra]

Re: Toshiba P55W Battery peekaboo

What is the best way to do this without having to remove any from the circuit board? There's a lot of varying techniques I've seen, is there a video that describes how to do it best/most effective?

Thanks!

[swofra]

Re: Toshiba P55W Battery peekaboo

Any guidance on the above? Wife has set a deadline by the weekend that she needs the computer to work on battery power and cheapest replacement battery I can find is $40 ... trying to avoid shelling out that kind of cash if it might be something on the mobo.