Electrical

2000 CHEVROLET BLAZER
170,000 MILES
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WADEDAVID
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  • 1 POST
With engine running my battery warning light illuminates and the voltage indicator drops to 9 instead of normal 14 and will stay this way for sometimes a few seconds to sometimes a few minutes and will then slowly rise back to normal and battery light goes off. I suspect a bad alternator but need further assistance because its erratic or intermittent. Thank you.
May 2, 2013 at 6:19 AM
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KHLOW2008
  • ✓ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
Symptoms indicates a failing alternator. The carbon brushes are worn resulting in intermittent contact.
When problem occurs, tap the alternator with a hammer and if the charging goes back to normal, that would confirm the alternator is bad.
May 2, 2013 at 6:44 AM
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