Macbook Pro shuts down unexpectedly

I've been having my Macbook Pro almost 2 years now and recently it's been shutting off unexpectedly while on battery power. I can run the battery down to nothing when I leave it on and shut the screen, but when I have it open it usually shuts down after about 20 minutes of use around 70-80% charge. I calibrated the battery like they suggested but that didn't seem to work. I also reset the PRAM. Then I ran an Apple Hardware Test and it gave me an error code: 4SNS/1/40000000:TG0D-128.000

Any ideas as to what that means or any suggestions on what to do from here?

Thanks!

The Apple Hardware Test error codes are not posted in the Apple KB and as far as I can determine, not generally available on line. Apple technicians have access to the codes of course, but that doesn't help you.

If your MBP runs OK from AC power without unexpectedly shutting down, you might want to try a new battery. You didn't mention how many charge recharge cycles are on the battery? You might want to download the free cocoanutBattery 2.7 and see what it says about the battery condition.

OK I downloaded coconut battery 2.7….here's what it tells me:

Max charge: 3724 mAh
Current capacity: 3724 mAh
Design capacity: 4600 mAh
23 months old
179 load cycles
temp 30.3 C
Power usage 15.4 watt

aren't these batteries designed for approximately 300 cycles? nothing looks out of the ordinary to me, but then again, I'm no expert!

Thanks for the coconut battery tip.

If you know someone with a spare battery, I'd try that. Odds are the system will run fine and won't shut down. If so, replace the battery. If you get the same symptoms, then start digging deeper. Also, might not hurt to reset the SMC.

Thanks for the help

I came across the same problem this morning when I was flying to FL. At first, I thought it maybe had something to do with the altitude or pressure or some other strange factor but I was completely lost as to why this was happening. I got my Macbook back in March of 09, it's a 13" unibody...this was a few months before they went "Pro". Is it likely that is the battery? Aren't these things supposed to last more than 2 years? Either way...this never happened to me before up until this morning.

I noticed that my boot time was longer when I started it...it normally takes about 30 secs or so but it dragged for a good minute or so. I was playing a game and was running SMC Fan App to monitor the temperature to make sure it would not overheat. After about 10 minutes it shut off. I turned on the lappy again and tried a different game...same deal. About 15 minutes into it it shut down and I figured it had to do with the games I was playing. I then switched to a movie and watched a good hour before it shut down AGAIN!

This post got really long but I figured any info on the matter could help us solve whatever the issue is. All help is appreciated, thanks!

Your battery is likely failing. Look at the previous posts in this thread and download the application that was suggested. How long are batteries supposed to last? That depends on how you've been using your machine and whether or not you operate it primarily on AC only or battery.

I did the SMC fix and currently testing to see if this fixed the problem. I really hope is not the battery cause I rarely use the computer on battery power...I mainly run it using the AC. I used the coconut app and here's what I got:

Max charge: 2601 mAh
Current capacity: 2601 mAh
Design capacity: 4100 mAh
23 months old
148 load cycles
temp 30.0 C
Power usage 15.5 watt

Is this normal?

Your battery is definitely lower than what it should be in order to provide an adequate amount of time off AC power. You can see that the current capacity versus the design capacity is almost 40% less. When a battery gets that low in capacity it can also become intermittent. You probably should think about replacing the battery if you intend to keep your machine for any length of time.

Oh that's lovely... =[

So...it seems like the average life of these batteries is 2 years eh? I did a bit more research and it seems like a whole lot more people are having the same problem, per the Apple support forums; not to mention, if you go to their site and look at all the ratings/reviews for the macbook batteries they are all 2 stars or below. People are complaining about how terrible they are and/or how they don't last like normal laptop batteries should. I love my computer but I dunno if I want to pay $130 every 2 years for a new battery...I mean, we're paying high enough as it is to get a good product...shouldn't they be made to last?