# Tune up and battery light staying in **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** ford, ranger\ **Created:** [August 18, 2020, 11:56pm UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891 "2020-08-18T23:56:34Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Janice-35](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@Janice-35](https://community.cartalk.com/u/Janice-35)\ **Post date:** [August 18, 2020, 11:56pm UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/1 "2020-08-18T23:56:34Z")
Ok I have 2 questions. 1 my alternator went bad in my truck and killed my battery. I replaced the alternator but the red low battery light won’t go off. How do I fix that? 2nd question I need to do a tune up on it the ranger it is a 4 cylinder but has 8 spark plugs. What do I need to do the tune up? Any help would be appreciated. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [August 19, 2020, 12:02am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/2 "2020-08-19T00:02:35Z")
> [@Janice-35](#): > > 1 my alternator went bad in my truck and killed my battery. I replaced the alternator but the red low battery light won’t go off. How do I fix that? Install a new battery, and hope you didn’t fry that new alternator. ![ALTERNATOR WARNING](https://global.discourse-cdn.com/cartalk/original/2X/8/801408206237ed3beac321bbd586b2af65b9d97a.jpeg) Tester ---
**Author:** ![Janice-35](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@Janice-35](https://community.cartalk.com/u/Janice-35)\ **Post date:** [August 19, 2020, 12:41am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/3 "2020-08-19T00:41:35Z")
I did get a new battery and that light still won’t shut off. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [August 19, 2020, 12:43am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/4 "2020-08-19T00:43:36Z")
What year Ranger? Tester ---
**Author:** ![Janice-35](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@Janice-35](https://community.cartalk.com/u/Janice-35)\ **Post date:** [August 19, 2020, 12:45am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/5 "2020-08-19T00:45:02Z")
It is a 1994 Manuel transmission ---
**Author:** ![oldnotdeadyet](https://avatars.discourse-cdn.com/v4/letter/o/a6a055/32.png) [@oldnotdeadyet](https://community.cartalk.com/u/oldnotdeadyet)\ **Post date:** [August 19, 2020, 12:59am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/6 "2020-08-19T00:59:10Z")
As far as your spark plugs go: that is not an easy job. Check out the videos on YouTube. The eight plugs are an oddity for a 4 cyl engine. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [August 19, 2020, 12:59am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/7 "2020-08-19T00:59:49Z")
There’s nothing special about your charging system. So a new battery/alternator should have solved the problem. Maybe the serpentine belt and components are worn? [https://www.rockauto.com/en/moreinfo.php?pk=8374548&cc=1137978&jsn=537](https://www.rockauto.com/en/moreinfo.php?pk=8374548&cc=1137978&jsn=537) Tester ---
**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:** [August 19, 2020, 1:03am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/8 "2020-08-19T01:03:37Z")
Do the spark plugs AND the wire set It’s highly likely that one or more wires will be damaged during the tune-up, so best to have a set on hand, along with those 8 plugs ---
**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\ **Post date:** [August 19, 2020, 1:16am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/9 "2020-08-19T01:16:15Z")
You may have to replace the alternator again. It sounds like you got a defective unit. It is very important that warning works as it supplies current to the exciter inside the alternator. ---
**Author:** ![tcmichnorth](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tcmichnorth/32/25126_2.png) [@tcmichnorth](https://community.cartalk.com/u/tcmichnorth)\ **Post date:** [August 19, 2020, 1:19am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/10 "2020-08-19T01:19:13Z")
Check all cables and wires at both ends of the alternator and same with battery cables. The connectors should be cleaned properly and no corrosion or damage along the cables. ---
**Author:** ![Janice-35](https://avatars.discourse-cdn.com/v4/letter/j/ea5d25/32.png) [@Janice-35](https://community.cartalk.com/u/Janice-35)\ **Post date:** [August 19, 2020, 1:44am UTC](https://community.cartalk.com/t/tune-up-and-battery-light-staying-in/168891/11 "2020-08-19T01:44:24Z")
Ok I will give that a try