# New battery, New alternator, car runs fine but I still have a check battery light **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** mustang, ford\ **Created:** [September 5, 2022, 2:20am UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213 "2022-09-05T02:20:26Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [November 20, 2024, 4:22am UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213/21 "2024-11-20T04:22:34Z")
The dealer diagnosed and repaired it under warranty. ---
**Author:** ![BEGE\_Ek13](https://avatars.discourse-cdn.com/v4/letter/b/c5a1d2/32.png) [@BEGE\_Ek13](https://community.cartalk.com/u/BEGE_Ek13)\ **Post date:** [November 20, 2024, 12:34pm UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213/22 "2024-11-20T12:34:09Z")
Noted. Thanks ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 20, 2024, 8:33pm UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213/23 "2024-11-20T20:33:31Z")
> [@bing](#): > > battery current sensor. The mechanics here can explain it. It’s been 10 days, OP is probably still waiting for a pro-mechanic explanation. I"m a diy’er, not a a mechanic, but I’ll try to help the best I can in my diy’er no-nothing way . My understanding is that sensor allows one of the car’s computers to measure how much current goes in and goes out of the battery. If the battery is fully charged and after that the same amount of current goes out than goes in, then in theory it will still be fully charged. This gives the computer a way to know when the battery is fully charged, or how much charge it still needs, and help the computer monitor the battery & alternator health. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [November 20, 2024, 8:35pm UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213/24 "2024-11-20T20:35:21Z")
If the op is impatient, they can just go to google and they shall find their answer. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [November 21, 2024, 2:28am UTC](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213/25 "2024-11-21T02:28:40Z")
> [@George\_San\_Jose1](#): > > I"m a diy’er, not a a mechanic THAT IS PATENTLY OBVIOUS [Previous page](https://community.cartalk.com/t/new-battery-new-alternator-car-runs-fine-but-i-still-have-a-check-battery-light/186213.md?page=1)