Battery and Heat

I was having problems similar to that, my computer would get so hot for no reason and the battery life would not last AT ALL, but what might help with cooling it down is if you get a laptop fan. After I got one my battery life lasted longer and my computer was definitely not as hot as before. Hope that helps!

did you check your "Activity Monitor" to make sure no process is eating the CPU resources?

Welcome to Apple Discussions!

There are a couple of things you can try:

First, run the Apple Hardware Test and see if you get any error codes. It may well be that a thermal sensor has failed or a fan is failing. Do both fans run at roughly the same speed or at very unequal speeds? And how fast are they running when the computer gets hot?

Another thing to check is Activity Monitor. Set it for all processes. Look for excessive CPU usage when you aren't doing much--you may have a process running in the background which is using lots of the CPU. This too can cause heat and shorten battery life.

It sounds like something has happened which is causing this excessive heat and the shortened battery life is a secondary effect. You need to track down what is causing the heat problem. Once that's found and fixed, your battery life should return to normal.

Good luck!

The Apple Hardware Test is on Install Disc #1 of the grey discs that originally came with your computer. You boot to it by holding down "D" as you start up.

As for the kernel_task, on my MBP the CPU is fluctuating between 1.8 and 2, the number of threads is 57, the real memory is 126.13, and the virtual memory is 1.15 GB Intel. Is yours comparable to this or much more?

http://home.sc.rr.com/mixedbag/MBP/Welcome.html

This is what i've been reading.

hi.

i was experiencing the exact same issues. super hot computer, shorted battery life. i have a MBP 15" purchased in september. after the battery life got pretty short recently, i took it in to an apple store, they checked the battery health and it appeared about right, but after a few more complaints she was very helpful and she replaced my battery.
everything is better. WAY BETTER. computer is not getting nearly as hot, battery is lasting a solid amount of time, and i have not heard the high power fan a single time. although it has only been a week, so far it has been a huge improvement.

go back to the store. complain a bit more. get a new battery.

good luck.

Your local Apple Store should be able to run the Apple Hardware Test for you from one of their discs, if you don't have yours with you. But when you do go home, make yourself copies of your install DVD's to take back to school with you--the licensing agreement allows you to burn a "safety" copy of each disc. You can keep these copies handy and use them to test your computer, and keep the originals put away in a safe spot.

Good idea to visit another Apple Store. Some of the earlier MBP's did run hot and this was considered normal. I'm not so sure that it really was, but there are Apple guys and there are Apple guys if you get my drift, and I think at least some of these guys think the excessive heat is normal and their eyes just glaze over when you mention it and you don't get taken very seriously. But if you get something concrete like an error code on the AHT, they have to take you seriously. And good that you have Applecare--it'll cover anything that's wrong.

But do check activity monitor next time your Mac gets super hot and the fans start to blast. Right now with Mail and Safari and Activity monitor open, the % idle on my CPU is 85%-89%. If you have just 2 or 3 applications open and don't have this much idle, look through the processes and see if something is hogging the CPU that shouldn't be.

Good luck!

Yes do keep after this--there is definitely something wrong.

Keep an eye on Activity monitor. I have 3 applications on, and the %idle is 95%-98%. The CPU usage is shown as practically all black, with just a few red and green dots along the bottom. Both boxes are mostly black. If you have one that is mostly green, like you posted earlier, then something's going on.

Do you have iStatPro? It's a widget you can download from the Apple site. You might post some actual temperatures when everything is so hot, and others of us can post some for comparison.

But definitely keep after this--this heat problem is not normal. And you need to find the root cause.

Good luck!