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FIXITMAN
FIXITMAN, Master Technician
Category: Mercedes
Satisfied Customers: 17143
Experience:  ASE MASTER CERTIFIED, AA DEGREE DIESEL/AUTOMOTIVE
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Check battery alternator light came on. Batter was replaced

Customer Question

Check battery alternator light came on. Batter was replaced last year. Can I test the battery and alternator separate? Car idles rough when engine is cold. Advice?
Submitted: 10 months ago.
Category: Mercedes
Expert:  FIXITMAN replied 10 months ago.

Hello, my name is Bobby. Thank you for the question. Can you tell me if you have a voltage meter to run you through some tests? If the battery light is on when the engine is running then chances are you have an alternator that is failing.

Customer: replied 10 months ago.
I don't have any tools. I'm trying to get some direction before I go to the shop?
Expert:  FIXITMAN replied 10 months ago.

Thanks for the response. If the car is starting fine then the battery should be just fine. The battery light coming on when the engine is running indicates a bad alternator. I would always check the battery connections first. If those are clean and tight then it is probably the alternator.

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