I have had a plethora of weird electrical problems with my new 2005 C6 convertible (11k on odometer) ranging from map light won't turn off, nav screen "Corvette" screen saver being on, car not starting, dead battery, Top won't go up. I've had it in the shop twice in the first two weeks that I've owned it. They've checked the battery and electrical systems and have found nothing wrong, other than having to reprogram the computer to get the top working again.

I believe I've figured out what I'm doing to cause the problems:

If I turn off the car before I shift it into reverse, I'll get a problem with the dash lights, nav screen & the map light and the green start button staying on after I've shifted into reverse. I push the stop button again and maybe get some of the stuff off, but it will go to alternate power. Battery goes dead or loses too much juice overnight. Then I put a trickle charger on it. If I get it started, the top will not raise. I've disconnected the battery before so it wouldn't go dead before I take it to the shop. Sometimes it wouldn't start even though the battery was charged. One time, just by touching the negative terminal, the hood light came on.

Its looking to me that if I put it in reverse BEFORE I turn the car off, then all is well. If I forget, then I turn the car back on, put it in reverse, then turn it off and all is well.

Perhaps this will help others.
Perhaps someone knows of why I have to do this.
And why do I have to shift into reverse to begin with??? I've never had a car before that cared what gear I left it in... I know the owner's manual says you have to or your battery could go down, but why? Seems weird to me...

 

Shifting to REVERSE before shutting off the engine is just the way it was designed, for who knows why. The 2005 also has a column lock that later models don't have.

It's just a rule you've got to get used to. You will kill the battery every time you don't do that. The owner's manual tells you that. You probably have a dead battery now. Get another battery.

Some forum members, with all different model year C6s, have had problems with the map lights staying on after shutdown. That's caused by inadvertently pressing and releasing the dash dimmer switch. That switch was designed that way to allow you to press it at night and turn on all the interior lights. Just press it again and the map lights will go out after you shut the engine off and get out of the car and lock the door. They will not go off immediately.

 

Never owned an car with Automatic Transmission that had to be shifted to Park?

 

Touching that battery terminal causing the hood light to turn on, is a major clue to at least part of what's happening. Either a bad battery or bad cable there and it needs to be fixed right away

 

The part about the top not going up is, after battery is discharged the windows need to be indexed so the the window s could lower before top will begin to raise.

Hope this will help!!!

 

I don't have a vert, so I didn't know to tell the OP this.

Here's how to index the windows, which you'll have to do after every battery reconnection.

 

While my Vette spend many days in the shop with no solutions found.
This week the problems came back and after charging the battery, it still wouldn't start. I decided to take the battery out and replace it.
But what did I find? The negative battery terminal was not tightened down! Doh. The nut to tighten it was only hand tight. It obviously has been like that since I bought it. Whoa. I grabbed a wrench and 10 seconds later, the car fired right up. I can't believe I didn't think to check that, but what is worse, the mechanics didn't either. They also did not know about holding the window switch up to reset the power top. They would make me wait around an hour as they reprogrammed the computer. I've been through that three times now. Ha ha. Live and learn.

 

Often times you will find more knowledge here than at your local dealership

 

I think you said it "lightly", there is a great deal of GREAT knowledge here and a lot more COMMON SENSE than at the dealer.

 

So very true!

 

Because of the Feds and theft protection the '05 MN6's had to have a column lock. To prevent column lock engagement while driving, the arcane reverse to shut down and engage the lock was engineered.

That being said, it should generally make no difference whether you shut down in reverse, or shut down and then go to reverse. Just as long as the car 'sees' reverse for a few seconds before you exit the car.
And because the cars needs those few seconds, there have been many episodes of DBS (dreaded battery syndrome). Probably caused by exiting the car too quickly, before the reverse mode shut down registers. Subsequently GM came out with a software fix to reprogram the BCM, to ignore these shut down anomalies, and let the car completely shut down. Make sure your car has been so updated!