Hello, I apologize if this isn’t formatted correctly. It’s my first time posting in here. I bought a 2023 Chevy Malibu with 1000 miles on it, and now I have about 12.5k miles on it. The other day, I got in the car and noticed that my radio was making a strange static sound. My backup camera was acting up, the volume knobs were delayed, and the transmission seemed to struggle when switching gears, although it was driving fine otherwise. There were no lights on the dash other than my tire pressure light, which is on because it’s below 30 degrees where I am. I pulled over and turned the car off, and my battery voltage went from 11.2 to 15.3 in a matter of a minute, kind of bouncing around. I’ve never seen the car running over 14.7 with the system reading it to me. I started looking into it, and some people say it could be an alternator failure, while others suggest a battery connection issue. I’m hoping to get some information that might help me narrow this down. Should I just pop the terminals and clean them? I haven’t changed the battery since I bought the car. I appreciate any help you can provide. Thank you.
15.3 volts is gonna cook that battery. You should have your battery health checked, which you can do at almost any auto parts store. Make sure that’s not junk first. After that, I’d look into the charging system and ground connections. Modern vehicles can act really strange if your battery is bad. I had a bad battery and a loose ground on my old Dodge; it would still start but the navigation system would reboot randomly and my gauges would stop working until I hit a bump, which fixed the ground temporarily. My advice is to check one component at a time and narrow it down. Start with the battery, then check the charging system and grounds.
Also, being a 2023 with low miles, you probably still have warranty coverage. Take advantage of that for anything you can.
Definitely have the battery tested and charged if needed. If it fails a load test, you should replace it. The charging voltage you mentioned is pretty normal. A lot of people think that the alternator charges the battery all the time like they used to 30+ years ago, but that’s not how it works now. GM uses sensors, components, data, and control modules to determine charging output based on battery state of charge, battery state of health, electrical demand, ambient temperature, and more.