Hey guys I have a 2020 HTC and I open and close the door a lot on my c8. I would say when I take it out to meets and let people sit in it anywhere from 200 to 300 times
in a single go and for 8 to 12 hours. Every now and then I start the car but when I'm indoors at a show I cant do that. I have literally got a dead battery/low no start from this. Is
there an option in the C8 to shut down all the electronics to save on battery or do I need to keep using my hulkman jumper and batter tender all day when I do this ?
Thanks guys!!!

 

The only way I know of to completely shut down the car is to disconnect a battery cable. You could get a quick disconnect to make that process easier.

OR, just leave the door open. After 10 minutes, the car will shut off power, and I'm pretty sure leave it off until you close and reopen the door.

 

Having some experience with this on a C-6, you need to get it back to the dealer and have it checked for a parasitic battery drain. There are so many electronics on these cars that can have gremlins. I will presume the car is still under factory warranty so there should be no charge to you. Don't just treat the symptom find the problem and fix it.

 

While I partly agree w. all of the above posts, if you're really doing it 200-300 times per meet with no recharge, I have to wonder if this might be normal depletion of the battery's charge to the point where it's done for/finito. Maybe not. Maybe it should have more reserve power. To some extent, it's up to the initial charge of/on the battery BEFORE you start one of these events, and maybe even what you do AFTER the event, assuming the car starts and moves.

Is the car fully-charged before this onslaught of visitors to the car? If the car does start after, do you fully-charge it up either in the garage or on the open road?

 

So the car is fully charged and It is garaged as well. Took it to the dealer and they put it on a booster or whatever to fully charge it to test and said its still within the range of NO replacement.
Fun fact and not even the mechanic knew this but the battery is part of the 3 year warranty lol. I did not get the extended or any extras.
So it may just be the fact of opening the door so many times.

 

I suppose if you are doing indoor shows and using power pretty constantly. You could explore setting up and auxiliary battery near the car and run some power to it. At first thought, you might simply plug the aux battery into the frunk port. However the wire for that is not large and thus would be prone to over heat if you are pulling a lot of amps. You might need to run a secondary line from the main battery terminals to a easy access location if you pursued that option. Just a thought to consider

 

I guess so. Esp. if there was no starting the car, or headlights on, etc.

 

Yes, it could very well be from opening the door, 200 times in 12 hours, which is once every 3.6 minutes. 300 times in 8 hours is once every 1.6 minutes. Opening it that often keeps the electrical system activated at a higher state of current draw. I measured the normal parasitic battery draw and reported it here:

https://www.corvetteforum.com/forums...e-battery.html

My measurements were consistent with what the shop manual says. The electrical system goes to sleep after being off for a while, but when you open the door the car electrical system fires up and draws 10-11 amps. The draw decreases gradually, after the car is locked, in steps, but from my measurements takes around 10 minutes to get back the lowest draw of 10-11 ma. When you open the door as frequently as you reported, the draw never gets back to its lowest state. Here is a summary of my test from the thread I referenced above.

After the car has been sitting for a while (more than 24 hrs), and before it is disturbed by any unlocking or opening action, I measured 10-11ma of current. That's pretty low. Then, I unlock, and then lock the car, and I move the key fob far away from the car. Immediately after the car is locked, and all the exterior lights go out, the draw is 10-11 amps. After about 30 seconds, it drops, in a step, to about 4.8 amps. At 60 seconds, it drops again, to about 2.8-2.9 amps. Shortly after that, before 90 seconds, it drops to 0.6-0.7 amps. I have to switch the meter range from amps to ma at this point. After 2 minutes, the draw is still around 570-580 milliamps (ma), which is still around the the 0.6 amps measured on the amp range. Around 4 minutes, it drops again, to around 300-330 ma. Somewhere around 10-12 minutes, it drops to the 10-11 ma, which I think is the final parasitic draw.

You may notice, in my test, I measured the drop after a unlock-lock cycle - and it does not include the period of time where exterior lights may come on. I suspect that if you are opening the door frequently, closing it, but not locking the car, the higher draw may persist for an even longer period of time. Any chance you are also demonstrating the HTC action?

 

This, or leave to the top down and just let people look.

 

Perhaps check out a rather expensive antigravity battery.

 

200 openings, door open 3 minutes each time. So Lookie Loo an lookie loo. Math says 600 minutes with all the interior lights on. Including the dash splash. Gotta kill the battery some. Nuts to do this. Put the top down and let folks look in from the top. What I'd do is keep the top up and the door shut. I'm not a dealer trying to demo a car. Folks can look in the window. Plus this makes them move on quicker. A good thing at most Saturday Show N Shine's.

 

Yeah... ALL they said!

 

Are you leaving the fob in the car when it's off? This is a known issue as the systems talk to each other causing drain.

 

If you are indoors at a show would you be able to gain access to a power outlet and use a battery maintainer? It might look silly but people who know these cars would understand.

Otherwise I would do as someone here suggested - open the top and keep the door closed.

 

Ouch it's great that you share that experience with people, but man that puts a lot of wear on your interior and if they do open the door a lot, wear and tear on the latch mechanism which is electronic.

 

So what I think I'm going to do is use the battery tender for a little juice and I can hide the wire to not get in the way of pics, then leave the door open and just slightly close it for pics. Tested and seems to work. Thanks man!
The fun is definitely letting people sit in it and the look on their faces when you say its ok. Like legit ppl don't believe me the first time I say it. I have pics of a few of the hundreds that I let sit in it at https://www.instagram.com/epicdreamchallenge/ and its priceless!
The reason I only have a few pics is because I'm usually so busy talking to people and hearing their stories I forget to ask.
Lots of great info there and thanks for the link! So I started lock the car after people leave around the 3rd or 4th event and it did really help to stop the draw but when I have 20 to 30 people around the car that gets impossible. That's when I move the key far away and not fully close the door till someone accidentally closes it lol. Then the cycle repeats. and I just leave the HTC open. way easier for ppl to get in and out of the car. And as you said if the car is off showing the HTC its a huge power draw.

I will for sure take a look into that! Thanks.
I enjoy it and kids love it. A lot of times I let young kids stand on the seat cause they are so short. Its a good excuse to wear the seats out to get GT3 seats

Naw I keep the fob as far away as possible.
I went to the next place i`m going to show it and Yes it has an outlet. Last place didn't lol. But yea, I will look into a good wireless battery maintainer for when outlets are not available. So I will be doing just that next time and let everyone know how it goes.

Thanks again everyone for all the info ! Your all awesome!!!