iPhone battery draining over night!

I have an iPhone 3g and have had it since the first day. The problem is it has been working flawlessly up till now. Now for some reason I am losing 20% of my battery per about 30 minutes of it just sitting and turned on. This is from a fresh reboot and power up. Even if I don't touch the phone or start any apps. I have wiped the phone and removed all of the apps and settings. The only thing I have configured on it right now is active-sync to my exchange server.

I know I can turn off 3G and such but the phone was working great and now all of a sudden the battery has just gone to almost unusable. I just can't figure it out.

Scott

Are you guys calibrating your battery? Meaning, your battery indicator could be off from actual battery life. I think Apple recommends after a full charge letting your battery run all the way down (ONE CYCLE) at least once a month. After it dies, I would charge it all the way back to 100%.

Here are many tips...

http://www.apple.com/batteries/iphone.html

I am having the same problem as svandive with my iPhone 3G after the latest update. I would like to add that the phone is heating up and the battery is draining really fast while on standby. I have WiFi and Bluetooth turned off. I restored the phone twice now and still have the problem.

Hisham

What type of mail account do you have on your phone?

I Have Microsoft Exchange and Gmail

Try deleting the Exchange account and then set it up again.

Thanks Deggie,
I implemented your recommendation. I will wait to see if it solves the problem.

Deleting the Exchange account and then set it up again did not solve the problem. It happened again yesterday, my iPhone got really hot and drained the battery.

Hi I'm having the same problem but I don't turn mine off at night. I bought a new iPhone 3G 4 months ago and it was working fine it lost about 1% over night until about a week ago. The battery is losing almost 50% over night. When I go on the Internet using 3G it uses about 1% ever 2 minutes which is not good. Any help?

There are some good tips here for battery saving...

http://www.iphoneuserguide.com/apple/2009/04/04/iphone3g/save-battery-life-on-ip hone-3g/


alternatively, you should possibly restore you're whole iPhone to make sure there isn't something gone crazy with the OS that is not shutting down one of your apps properly.

I had this with Google Maps not closing properly, and thus the GPS stayed on ALL THE TIME. a quick restore fixed the problem.

Hi I restored my iPhone 3G and now it's working fine. If you are going to restore your iPhone 3G when you plug it into iTunes for the first time after restore select restore from back-up.