Battery light stays on, alternator tested good

200,000 MILES • 6 CYL • 2WD • AUTOMATIC
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BRUCE3119
  • MEMBER
  • 1 POST
Hi, the battery light on my vehicle has been coming on frequently, and I lost all electrical power a week ago. I was able to get it to a repair shop, and they checked out the electrical system. Everything checked out fine, and they were reluctant to recommend a new alternator. They drove and tested it every day for a few days and everything ran fine. I have driven it since, and the battery light stays on constantly now, but now other issues. Any ideas where I should look next to resolve the issue?
Oct 22, 2018 at 6:48 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good afternoon.

The reason the light is on is from a bad diode in the alternator. It can still charge but not turn the light out.

Check the battery voltage with the engine running and it should be 14 to 14.5 volts

Also, check the AC volts.

Roy
Oct 22, 2018 at 7:10 AM
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