Battery light on my alternator is making 13.6 volts

2000 FORD WINDSTAR
138,000 MILES • 3.0L • V6 • 2WD • AUTOMATIC
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LAKERHATER4
  • MEMBER
  • 1 POST
My alternator is making 13.6 volts DC. When I turn on all lights and A/C it goes to 13.5. I did this at idle without increasing rpm. Do I need another alternator?
Jul 4, 2021 at 5:57 PM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good morning,

The charge rate should be 14 to 14.5 volts. That low voltage tells me it needs to be replaced.

https://www.2carpros.com/articles/how-to-replace-an-alternator

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I attached the wiring diagram for you and the procedure.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Roy
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Jul 4, 2021 at 6:58 PM
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