# Ford battery light on when idling **URL:** \ **Category:** General Discussion\ **Tags:** ford\ **Created:** [November 2, 2012, 6:19pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308 "2012-11-02T18:19:30Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![BillMac](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BillMac](https://community.cartalk.com/u/BillMac)\ **Post date:** [November 2, 2012, 6:19pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/1 "2012-11-02T18:19:30Z")
Battery warning light came on a couple of times when driving to work in my 2000 F-150. I had thought that the instrument lights had looked dim for a couple of days. The warning light was only when the truck was idling and the warning went off as the truck was moving. ---
**Author:** ![shadowfax](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/shadowfax/32/13026_2.png) [@shadowfax](https://community.cartalk.com/u/shadowfax)\ **Post date:** [November 2, 2012, 6:41pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/2 "2012-11-02T18:41:27Z")
Have your alternator tested. Battery too, while you’re at it. ---
**Author:** ![BillMac](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BillMac](https://community.cartalk.com/u/BillMac)\ **Post date:** [November 2, 2012, 6:48pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/3 "2012-11-02T18:48:16Z")
Battery is less than a year old. ---
**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\ **Post date:** [November 2, 2012, 8:05pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/4 "2012-11-02T20:05:16Z")
Batteries, like any other part, can be bad off the shelf, Bill. New does not = good. Get the battery and charging system thoroughly tested. And I wouldn’t be surprised if the belt tensioner was weak. ---
**Author:** ![badbearing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/badbearing/32/10683_2.png) [@badbearing](https://community.cartalk.com/u/badbearing)\ **Post date:** [November 2, 2012, 8:11pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/5 "2012-11-02T20:11:40Z")
Low idle ? ---
**Author:** ![meaneyedcatz](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/meaneyedcatz/32/692_2.png) [@meaneyedcatz](https://community.cartalk.com/u/meaneyedcatz)\ **Post date:** [November 3, 2012, 8:00am UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/6 "2012-11-03T08:00:07Z")
theres a chance you need a new belt, the belt might be slipping on the pulley. ---
**Author:** ![BillMac](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BillMac](https://community.cartalk.com/u/BillMac)\ **Post date:** [November 3, 2012, 10:25pm UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/7 "2012-11-03T22:25:32Z")
Truck now towed to the shop. While driving home last night, instrument panel stopped working, headlights dimmed; the lower the rpm, lower the power. Pulled over. Truck would not restart. Battery would charge with a jump, but not keep the charge. Now just hoping for good repair and cheap bill! Will let you want the mechanic says. Thanks for all the input. ---
**Author:** ![BillMac](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BillMac](https://community.cartalk.com/u/BillMac)\ **Post date:** [November 16, 2012, 5:08am UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/8 "2012-11-16T05:08:13Z")
$500 later we had the Altinator and Serpentine belt replaced. Running fun now. Thanks everyone for the input. ---
**Author:** ![EllyEllis](https://avatars.discourse-cdn.com/v4/letter/e/f14d63/32.png) [@EllyEllis](https://community.cartalk.com/u/EllyEllis)\ **Post date:** [November 16, 2012, 8:14am UTC](https://community.cartalk.com/t/ford-battery-light-on-when-idling/75308/9 "2012-11-16T08:14:24Z")
Well, I figured it was the alternator but wouldn’t be happy about the $500.