Can't Charge Battery;hear relay clanking??

[Lew]

This is my first dead battery ritual on the '07 Z.

After much tail chasing I finally got into the car and tried charging the battery with a trickle charger......

Tried both directly at the battery and at the under-hood points recommended in the owner's manual.

No Go!

I hear a relay clanking near the front headlight, the dash lights flash in sync with the relay clanking......yet, no charge is happening.

Any suggestions for some way to charge the battery without disconnecting it.....and will that stop the relay???

Do I just need a larger charger?? I try to avoid those as they usually destroy the battery with too much heat.

Thanks for your help!

[SonOfaDragRacer]

Your alternator is bad.

[Top Cog]

...or the battery plates are shorted out.

[Lew]

The relay clanking was the security system attempting to honk the horn. The trickle charger did not have enough power to make the horn actually honk.
This was determined by connecting one of those mini jumper batteries upon which the horn started honking and the key fob was able to quiet the horn.

Now I am trying to do the trickle charge again...sigh.

[gasboy]

needs a new battery.

[Rauchy]

Lew,

I just went though this on my new 07 Z06. Let me share what I have learned. First, there is some new programming required that relates to the part of the car that reads the key fob. With that reprogramming my battery drain is now nil.

Before I had the reprogramming done however I went through the dead battery and charging routine a few times. The battery was checked and it was fine. So I quit trying to charge with interior lights on from the hatch being open and I disconnected the terminals at the battery and charged it properly.

When I completed the charge I reconnected the battery. Have the key fob handy and when the lights and alarm go off just hit the door unlock button.

I monitored the battery drain at the positive terminal at the fuse block under the hood. That way I could do it without opening a door. I just left the hood open and the multimeter set there and it went from 12.7 volts down to 12.2 volts (thats close to drained) in about 3 days.

After the reprogramming I repeated the voltage monitoring and I was losing about .02 to .04 volts per day. I can live with that.

Disconnecting the battery does not lose any of your settings and the only downside is the alarm goes off when it is reconnected, but if you are going to let the car sit for more than a week that might not be a bad idea.

[Lew]

Tell me more about the reprogramming!
Is this a GM notice of some kind that I can tell the dealer about?
Is this Tech II programming or key fob programming?
Thanks,

[Speedster]

I drive my 2006 Z06 only on weekends. About 3 months after it's May, 2006 delivery, the battery would not crank the engine. Jumped it, went to the dealer, and they replaced the battery. Three months later, same deal, and I installed a Diehard. Feb. 2007, another dead battery, although honoring all the suggestions (park in reverse, use the parking brake, lock the doors with the fob). Insisted the dealer find the cause. They applied "reprogramming" to reduce the drain caused by a receiver in the dash. The Corvette trained mechanic managed to miss a few steps in the reprogramming, after which the car refused to recognize the fob, unlock, start, nothing...dead. Long story, but after 18 business days at the dealer, Chevy replaced "N6620 - Wiring and/or connector -power and grounds distribution, N4800 - replaced module, computer control body and R4480 - replaced receiver remote door/rear compartment lock", plus another battery. Although I had already called an attorney about the NC lemon law, I was very pleased to have the car back. You guessed it, in mid May 2007, the battery would not start the engine. I've resorted to a battery tender ever since...no problems. Hope you have better luck with the reprogramming than I.

[GlennSullivan]

2006 C6Z Here, same exact crap. I sometimes only drive my Z once every couple of weeks. And EVERY TIME I would try to start it after that time lapz, I have a dead or almost dead battery. I resorted to the Battery tender and the problem is solved. Pretty shitty when I can leave my other 2 cars for months with no problems.

[Rauchy]

Lew,

Sorry for the delay in responding. I am not suggesting I have the solution, but on my car the only way to get a decent charge was to disconnect the battery and charge it independently.

It turns out the part of the car that senses the key fob needed an upgrade to the software. It has been several weeks since that change and the battey appears to be holding its charge.

I am going to find out for sure because we are leaving for 10 days and if the car still has enough juice to start the problem has been cured. Apparently there was a service bulletin on this.