when I'm jump starting the car the battery reads 11.7 volts. Then when I try to start it the starter noise gets lower until i just hear a bunch of clicks. Do I need another battery...this one's less than 1/2 a year old.

 

What's the terminal voltage while cranking NOT being jumped ?
A good battery with a good starter should stay above 10 for 30 seconds.

 

when i crank it it drops down to like 6 volts then 5 then 4, 3 etc. then the starter just clicks..

the instrument lights dim and flicker when it cranks.


goes up to 11.5v after I stop cranking.

I have the negative battery cable going to the bracket on my alternator. I sanded the metal it touches.

 

I would try taking the battery to the local auto parts store to test. It may be defective or something. And if the battery tests fine, your starter may be drawing too much amperage.

 

It's a bad battery. I had a duralast do this to me once, in the dead of winter. I hooked a voltmeter up and watched . 11.5 volts while not cranking. I tried to start the car and once it dropped to 7 volts I didn't go any further. IIRC, anything below 9 volts while cranking is a dead cell.

There is always a possibility the starter COULD be shorting the battery, but like has been stated a quick test at a local parts store will determine whether or not the battery is bad.

Don't let them feed you any BS either. They tried to blame the wiring in my car for the failure. I've been running an optima battery for a year now with no problems.

 

i dont think its the battery, i have the same problem and i jumpered it with my truck battery (yukon) and it starts to try and turn over and then starter just clicks like crazy... i tried a new alt also, im thinking either refurb starter gave up or a short somewhere... someone told me to add shims that i forgot cuz the teeths have to be within tolerancewhen trying to turn fly wheel, nto sure tho, will try this weekend, anyway, thats my 2 cents.... good luck

 

I've seen people try and jump a battery with a good one and got little help. They said they tried to charge it for all day and it still wouldn't start it. I pulled off the battery cables and discovered so much crud between the cables and the dirty battery terminals that power couldn't get through. Sometimes a simple cleaning up the connection makes a world of difference. Check it out, and don't charge the battery with the cables still connected! Just sayin'
But Opyders, sounds like a defective battery