Battery only 3 months old, but dead. (2007)
 

Hello, I replaced a relatively new battery 3 months ago on my 2007 Boxster.

I went away for two days this weekend, the porsche was in my garage
Yesterday I returned and the car wouldn't start.
When I turn the key I hear it clicking and the lights flash but it wouldn't start. Seems like a dead battery. The lights and radio were not left on.
SO I jumped it from my wife's car and it started. I drove around awhile and I thought it would be fine.
The next morning the same thing happened. Turn the key, hear clicking, lights flashing but wouldn't start.

My battery is only 3 moths old, and I didn't get the cheapie battery either.
Has anyone else experienced a battery problem similar to this one?
What are the common causes?
Is there any way to measure the current drawn from the battery while the car is turned off?
Thanks

One more thing I will mention.. after jumping it, the air bag indicator was red on my dashboard.
Could there be a problem with the airbag that is causing the drain?

Boxsters do tend to run batteries down quickly if left for long without a battery tender, but a 3 month old battery should be able to be left for weeks, not days. Have you had a load test done? The battery could have a bad cell in which case you should be able to get a new one under warranty.

If the battery is still good (it probably is not), you need to make sure the alternator is charging it fully. Voltage should be around 14 or more, checked with a multimeter between the battery terminals with the engine running. DO NOT disconnect either battery terminal with the engine running! Have you checked if there is a parasitic drain when everything is turned off? Check the amperage draw between the battery negative terminal and the negative wire. For this you do have to remove the wire from the terminal, but only with the engine off. You should also remove the frunk light bulb so you don't get a reading from it. Here's a pretty good YouTube video:

https://www.youtube.com/watch?v=zdIKNnwEjIs

Maybe you got a defective battery ? Take it back to where you bought it. They will test it and the alt. Free diagnostic.

^^^^ What he said. Rare for a battery to go bad in 3 months. Could be a bad alt or voltage regulator.

Uh, I could have sworn that I just said that...:rolleyes:.

Exactly how long is "drove it around a while" ? It may have not had enough time to re-charge. A small maintenance charger is inexpensive, and a wise purchase, though 2 days isn't enough time for it to go dead unless something was left on, like a trunk light.

I just replaced the battery on a one year old Toyota. The service manager said that it is not that unusual. My parents had to replace the battery on a 3 month old Cadillac. It happens.

I had the battery checked out... they said it was fine and recharged it.. unfortunately looks like next step is taking it to the porsche dealer

OK, fine. But did they check to see if the alternator was charging it, and if there was any parasitic drain...? Easy enough to do :rolleyes:.