Well title says it all... if my car sits for three days the battery will die. Checked the alternator replaced like 4 battries. All that is installed is Altezza rear light and a deck? What could be killing my battery and what can i do to diagonse the problem????

 

Test the Alternator at any Auto store. Check the wirings to the deck.

 

Remove the negative battery cable, hook a test light or meter in the amp setting between the negative cable and the negative post. If the light lights or you show excessive amperage on the meter you have excessive draw on your battery. Pull fuses until the light goes off or you see the meter reading drop. The fuse that results in the drop is the circuit that has the problem.

 

Replace the grounds running to the battery, as they will be corroded after 10+ years of use.

 

How old is your battery? Have you tested it to see if is good?

S

 

Battery is 3 weeks old. Tested it and is good.

 

You know that is a really good idea.. thanks alot i will try it out and see.

 

could be that too but i dunno thnx.

 

Seriously, take it in. I have had the same problem and was pulling out my hair. Turned out it was a damaged/broken sensor for the stock factory alarm system that told the car to go into sleep mode. It wouldn't do that and the car was staying awake thereby draining the battery. It was for the trunk.

I never would have found it. And I'd be bald.
that would have been bad.