OK I must be going nuts. I installed a new battery about a week ago. The old one which wasn't that old barely cranked my Z. The new one seemed fine and after a couple of days of non use is dead and I mean dead. With a jump from by other car I get the interior lights and the ticking sound but no turnover. What the hell is going on here? HELP

 

I'll wager money you have a bad connection. check the grounds at the frame and the engine. Dont forget the positive battery cluster at the passenger fender.

Put a voltmeter across the battery and you should see about 12.6V. Now move the lead from the negative terminal to a clean spot on the engine with the other lead still on the +battery terminal. The reading should be the same.

 

Connections or bad/incorrect new battery.

Seen new batteries that were junk because the terminals actually turned inside the case.

 

I've had a relay stick and drain that battery on my Jeep.
Let me tell ya, that was fun trying to find that one.

 

I had a slow "leak" in my electrical system. Somewhere in my powerseat/rear defrost there was an open circuit. You might want to troubleshoot the possibility of an open circuit somewhere.

 

It appears to have been the light in the center console which satys on since the button isnt being depressed