Title says it all. The truck runs fine even though it has 200,000 miles on it. When I accelerate hard, the battery light comes on. Performance is fine. This is even under conditions when there is not much load (i.e. no AC). I think I put a new battery in it a couple months ago. Why would acceleration cause this?

Thanks,
dbteeitup

. Check drive belt condition and tension.

. Alternator brushes may be worn and bouncing at high rpm. Try replacing the brushes and cleaning the slip rings with #240 abrasive cloth. Replacement brushes (RX101) cost $16.99 at AutoZone.

. Perform the tests in this link:

https://www.askmehelpdesk.com/cars-t...ml#post1973613

Should be an easy fix.

Check the condition of the connector at the alternator. Wiggle it while engine is running. If light turns on, you've found the problem. Engine movement from heavy acceleration can pull on the wire connector at the alternator. Real common in older Fords.