I replaced the battery in my corvette after it had drained twice fully from some long trips on my part and my family not remembering to drive the car to keep it fresh. Now i'm on a second battery in 6 months and am concerned about whats going on. I feel like my alternator and electrical system may be working properly but i have a radar detector and ipod hardwired to the car. My issue is if i forget to disconnect the detector and ipod when parking they keep draining power from the battery. Basically my question is do you think that the constant drain from these items and the battery going fully dead would be enough to make batteries fail to hold charge.
FYI...when i drive the car everyday it runs fine. i monitor the stock voltage meter while i drive often and while running the voltage is steady at 14v and when at a stoplight sometimes may drop down to 12.9v at idle and goes back up once i start moving again.

 

Draining and recharging the batery will definitely shorten its life. You may have a parasitic drain to which C5's are susceptable. Mine was the drive seat lumbar motor. Best bet is to get a float type mini-charger to keep the battery charged while the car sits.

 

Yes, that can harm a battery. You may want to look into finding a switched power source for your detector and Ipod.

 

These cars don't like the battery to go dead and then charged. Some kind of inline on off switch or switched power on for the two items you mentioned would help.
There is a lot of info on the forum re: dead battery. Do a search to see other good suggestions.

I thought the 12.9 @ idle seemed to be low.

Bill Curlee is the guru on this stuff-hopefully he sees this and posts.

 

I had a similar problem on my 50th,went through 2 batteries less than a year. 3rd battery has lasted over 3 years. Charging system was fine.

"My issue is if i forget to disconnect the detector and ipod when parking they keep draining power from the battery. Basically my question is do you think that the constant drain from these items and the battery going fully dead would be enough to make batteries fail to hold charge."

In my opinion and past experience you can only charge a battery some many times until it develops a bad plate/or dead cell.

It is possible you just got a crappy Battery the 2nd time, happened to me

 

HI-
You might want to check the battery terminals !! IF You changed battery's SOMETIMES THE ORIGINAL SCREWS can be tight BUT NOT MAKING CONTACT FULLY ... they sell shorter terminal screws w/ THREADS ALL the Way to the ends !!!! It worked 4 me when installing an excide battery !!!!!
Good luck !!!!

 

i bought a charger for my motorcycle and hooked it up to the battery just now and it reported that the battery was "bad". I guess taking it back to the auto parts store today will get me another battery. I may put an inline switch at the negative terminal to kill the battery while not in use (in addition to hopefully remembering to disconnect the accesories in th car). would the negative or positive terminal be best for a switch?

 

Your C5 battery is CONSTANTLY being drained when the engine is OFF> The good side of that is the draw is only 0.020 milliamps. With that little bit of current draw a good fully charged battery will/should last for 2-3 months without a problem!

The C5 (as stated above ) is susceptible to things drawing current when there NOT suppose to. They get stuck on or draw current cause they get defective. You need to conduct a battery current test when the car is OFF and the BCM is in the sleep mode. I have a sticky that details this procedure. Its under this:

http://forums.corvetteforum.com/showthread.php?t=896875

Conduct a battery current draw test and see how much current that your drawing when the car is OFF!

I also agree that you need to connect those aftermarket devices to a SWITCHED POWER source. There is one connection specifically for accessories in the passengers foot well. One of the wires has a ACC/ignition ON wire.

 

I was having trouble finding what it could be. Started once when my horn began to go off by itself. Had several months of battery would die if not run for 3 or so days, (had car for a few years, would last for 3 months easily in winter before). Replaced battery twice. Pulled fuse for horn previously. Found the relay for the horn was warm when car had sat for 9 hours!! Replaced relay, hopefully that was the issue.

 

I had a similar issue. There was no extra electronic items hooked up but my battery would go dead after sitting for a day or two. This only started after I killed the battery after leaving the my car sit for 3 weeks without driving it.

I bought a smart battery charger to keep it charged but I realized the tender would always be charging the battery. It would never just stay charged. The charger's light was supposed to turn green when charged and then just trickle in the juice as needed. I then noticed it would only charge up to about 11.6 when not running. Read - not holding a charge.

So I bought a new battery. Now when I put the charger on (100% of the time the car is in my garage). The light on the charger is always green and she's fully charged. No more problems. Stays at about 12.4 when not running. It's supposed to be 12.6 without any draw.

Case and Point - my battery was shot and it did not hold a charge. It was also 4 years old. And the car was not driven much prior to my buying it. I bet it was dead many times in the past.

As you have found out you need a switch for those toys of yours otherwise you'll keep chewing up batteries.

 

Try a Battery Tender they run $49.00 to $59.00 at Ecklers, it will keep battery up when car not in use, also for cars stored over winter.