# Battery light **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** mercury, sable\ **Created:** [September 28, 2010, 5:26pm UTC](https://community.cartalk.com/t/battery-light/55707 "2010-09-28T17:26:50Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![bisstess](https://avatars.discourse-cdn.com/v4/letter/b/8dc957/32.png) [@bisstess](https://community.cartalk.com/u/bisstess)\ **Post date:** [September 28, 2010, 5:26pm UTC](https://community.cartalk.com/t/battery-light/55707/1 "2010-09-28T17:26:50Z")
2000 Mercury Sable wagon, 3.1 DOHC engine with 140,000 miles. Battery light came on, mechanic said that it was the alternator. Replaced the alternator, and now the battery light comes on intermittently, especially when loading the engine (going up a hill). Mechanic checked the output of the alternator and said that it was putting out correct voltage. What could be causing the intermittent battery light? ---
**Author:** ![lion9car](https://avatars.discourse-cdn.com/v4/letter/l/59ef9b/32.png) [@lion9car](https://community.cartalk.com/u/lion9car)\ **Post date:** [September 28, 2010, 6:15pm UTC](https://community.cartalk.com/t/battery-light/55707/2 "2010-09-28T18:15:50Z")
The serpentine belt could be slipping. Belt dressing could be used to test for this. The battery cables could be loose or corroded. ---
**Author:** ![bisstess](https://avatars.discourse-cdn.com/v4/letter/b/8dc957/32.png) [@bisstess](https://community.cartalk.com/u/bisstess)\ **Post date:** [September 28, 2010, 6:32pm UTC](https://community.cartalk.com/t/battery-light/55707/3 "2010-09-28T18:32:03Z")
Thank you… I had the mechanic clean and tighten the cables. Waiting to see if the light comes back on. ---
**Author:** ![bisstess](https://avatars.discourse-cdn.com/v4/letter/b/8dc957/32.png) [@bisstess](https://community.cartalk.com/u/bisstess)\ **Post date:** [September 30, 2010, 12:01pm UTC](https://community.cartalk.com/t/battery-light/55707/4 "2010-09-30T12:01:58Z")
The battery light did not come on for two days. Yesterday it came on three times in 5 minutes. This time in normal driving conditions, not loading the engine as in going up a hill. No noise from the belt slipping. Any other ideas??? ---
**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\ **Post date:** [September 30, 2010, 1:15pm UTC](https://community.cartalk.com/t/battery-light/55707/5 "2010-09-30T13:15:36Z")
Your replacement alternator could be bad. It could be the wiring to the alternator. It could be the ground strap to the engine. It could be the PCM (probably not, but possible). It could be wiring under the dash. It could be an issue with the instrument cluster. It could be the battery internally shorting (unlikely). (This assumes that the battery cables are okay and the belt and tensioner are okay.)