Not sure if my battery's getting a little weak but can someone tell me what the voltage on the battery is when engine is off on a fully charged battery?

 

12.6v

 

Also, try starting the car and testing the voltage with it running. Should read 14v or higher i think.

 

take it autozone they do free battery testing

edit: just because the voltage is right doesnt mean its ok, ive seen many batteries with 12.6v but have no capacity

 

Thanks after got home my mini battery showed 11.8 after not being started for 5 days. I charged it for a couple hours on the trickle and next morning I got 12.6 . The battery is only about a year old but it's not for quite a few months while the car was down last year.

 

I always use the 15 minute test on any vehicle without a voltage indicator.

I should have enough battery to start the car. Drive for 15 minutes. Stop and shut off the motor. Turn key to accessory, listen to music for 15 minutes and be able to start the car again.

Once the battery starts going bad, it will still start and drive, but it fails the 15 minute test.

My battery reads 12.7 right after driving, drops to 12.6 after sitting for a few hours. At the end of my 15 minute test it reads 12.4 but still starts the car. (Readings from my Apexi turbo timer)

 

Hey that's a good idea I'll try that

 

I have the red top optima relocated to the trunk besides the fact its dead every two weeks it does struggle to start the car fully charged .....starter jus feels slow turning over