Q: I put in a new battery. Alternator tested fine with meter. What else could it be? Battery light comes on again.

asked by on December 21, 2016

Battery tested at 12.6 volts not started. Started it, it tested at 14.30. Running most accessories it went down to 14.20. But my battery light comes on the first 5 minutes it runs and after 15 minutes of running the lights flicker. What else could it be?

My car has 166000 miles.
My car has an automatic transmission.

In order to know if the light is coming on for the alternator you will need to test at the alternator when the engine is at 2,000 rpms to see if voltage goes over 15 volts. If it does then the alternator needs replaced.

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