Recently replaced alternator on my 2003 Pontiac sunfire now battery light is on how can I fix
The light usually means there is a problem with the charging system. I would take it to a shop, preferably a starter & alternator shop as they could test the system right there for you.
Check the tension and the routing of the serpentine belt you installed after replacing the alternator. Is it loose and slipping? If so, it will not turn the alternator you installed.
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