After starting the engine a "Some functions will be disabled to protect the battery" warning light comes on. I can't find any reference in my owner's manual that addresses this light. Yes, the car has been sitting for a week, but can anyone cite a page number where I can read about this light?
After a few miles of driving the light came again when re-starting the vehicle.
Pressing the "dismiss" button extinguishes the light.
Regards,
Patrick

 

what does the battery voltage show in the dash if you set that info to show your battery, when the engine is off, and just the ignition is on showing the instruments?

 

Page 86 of my 21 manual has the following: Charging System Light
The charging system light comes on briefly when the ignition is turned on, but the engine is not running, as a check to show
the light is working. It should go out when the engine is started.
If the light stays on, or comes on while driving, there may be a problem with the electrical charging system. Have it checked by your dealer. Driving while this light is on could drain the battery.
When this light comes on, or is flashing, the Driver Information Center (DIC) also displays a message.
If a short distance must be driven with the light on, be sure to turn off all accessories, such as the radio and air conditioner. Find a safe place to stop the vehicle.

 

Patrick, only 1 week and you have a problem. That's not supposed to happen.
How old is the car\battery?

 

it's a 2023 purchased in November 2022. I can't find a reference for this light in the owner's manual.

 

Age is not always a determining factor for replacing the battery, however, it's always best to keep it on a tender, regardless of how often you drive it. I compare it to having a full tank of gas, an empty tank won't start a car, and neither will a depleted battery.

 

Just to be clear, the car started without hesitation. The warning light (msg) was advisory., I think. Where can I find the meaning of it? This message was not the charging icon light on. It was a message in the area where you might see "hill assist active".

 

8 Vettes, 34 years, more than 1,000,000 miles - never a tender

 

First I believe what mikes 1967 found is all I have even seen. The light ONLY comes on when starting as noted to let you know it's working. If the battery light is on after starting it could be an issue with the alternator. The charging system is computer controlled. Under most conditions the battery ONLY charges to 80%. Like most new cars that is to reduced wasted power charging higher. I use my car, a DD but retired don't need it every day. If it sits for say 4 day the voltage as displayed on the dash will be ~14.5 volts. It will bring the battery back to 80% charge. After ~25 miles having achieved that 80% charge it will drop to 13 to 13.5 volts which is only enough to supply current needs, i.e. AC, sound system etc BUT not sufficient to charge the battery further. Suggest putting Voltage on the dash display and watch and see how it charges.

As far as needing to put the C8 on a charger. I have but never used the GM equivalent CKET charger. No need. The C8 (as the C7) shuts off all significant power after ~10 minutes. You can test, turn on the Map Lights, open Frunk and Truck and those lights are off after <10 minutes. I have been on vacation for 3 weeks with my two C7s and 2020 C8 and have zero issues starting the car not left on a charger. Some posts quote car at the airport for 5 weeks and no issues. Now if a use once a week car, sure leave it on a charger. But when I want to drive, I want to get in the car and go. Same when I return.

Quantifying, Member Andybump measured the parasitic current draw at after ~10 minutes it was 15 milliamps. That is very low.

This Pic is made from my C7 4 volume service manual. As noted, a battery at 80% charge can reach 59%, enough to start the car with 25 milliamps after 33 days. 15 milliamps as AndyBump measure would be longer.

 

I checked the 2024 manually pretty thoroughly and there is nothing mentioned on the warning.
I did find a related topic on Corvette Blogger.
State of Battery



Found in the Manual :

 

Having the alternator NOT enter fuel savor mode sounds like a win to me.

 

All modern cars are using that method of charging, computer driven to reduce gas consumption for less CO2 emissions. In daytime driving that is what it will be.

We'll see what other things car companies will be required to implement if the current EPA requirement of cars on average needing to achieve 49 mpg in 2026 (versus the prior that was stopped of 54 mpg in 2025.) The new requirement was reinstated April 2022. Get ready for much more things like forced Stop/Start mandated etc.

 

So, are you seeing a light, or a message on the DIC, or both? What you described sounds like a message on the DIC. I have never noticed the warning light but the manual indicates that there is a battery warning light. As for messages, based on forum posts we know that the car is capable of displaying lots and lots of different messages, very few of which are described in the manual.

There is a little more in the Service Manual. The car has an electrical power management system that will detect certain conditions and go into "load shedding", which will disable certain functions.

"The load shed operation is a means of reducing electrical loads during a low voltage or low battery state-of-charge condition.
The idle boost operation is a means of improving generator performance during a low voltage or low battery state-of-charge condition."

It lists some messages that might appear as a result - I could not find the message you described, but here are some example messages.

BATTERY NOT CHARGING SERVICE CHARGING SYSTEM or SERVICE BATTERY CHARGING SYSTEM .

Rear Defrost, Heated Mirrors, Heated Seats, HVAC cycled OFF for 50% of
their cycle. The BATTERY SAVER ACTIVE message will be displayed on the
DIC

 

Batteries are all over the ballpark, as many can attest to. It and its connections are always a place to start with our rolling 'puters. Good luck.