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How To Test A Car Alternator | 5 Simple Steps

Having charging problems or see a battery light pop up on your dash? LMR explains how to check & test your alternator with only 5 simple steps.

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When your car's charging system is not performing up to par, you run the risk of being left stranded on the side of the road. When you see a battery light pop up onto your dash, you know that there is some type of fault in your charging system. If your battery is fairly new, the most likely culprit is your alternator. Follow along as LMR walks you through the quick and easy steps on How To Test Your Alternator.

Tools Needed

  • Voltmeter

How To Test An Alternator


  1. Remove battery terminals and make sure these are 100% clean from and buildup of corrosion. Clean these to ensure proper continuity for the charging system. Reconnect for testing.

  2. How To Test A Car Alternator: 5 Steps  - How To Test A Car Alternator: 5 Steps

  3. Test the battery voltage, at rest this should read between 12.5 and 12.8V on average. If the batter is low, then charge the batter to meet these specs.

  4. How To Test A Car Alternator: 5 Steps  - How To Test A Car Alternator: 5 Steps

  5. Check over all vehicle grounds to ensure these are up to par.

  6. How To Test A Car Alternator: 5 Steps  - How To Test A Car Alternator: 5 Steps

  7. Inspect for proper belt alignment and any possible belt slippage, these can affect overall output of the charging system.

  8. How To Test A Car Alternator: 5 Steps  - How To Test A Car Alternator: 5 Steps

  9. Test the battery and look for 13.5V-14V with the engine on and all accessories off including lights, a/c, and radio. This can be done at the battery terminals with a quality digital volt and ohm meter. This should be a normal reading for these setups. If you do not have access to a DVOM, then you can remove the alternator from the car and most local auto parts stores will test these for free.

  10. How To Test A Car Alternator: 5 Steps  - How To Test A Car Alternator: 5 Steps

That's it! These 5 simple steps are sure to help with checking and testing your alternator. Take matters into your own hands by avoiding the inconvenience that it takes for a professional to diagnose something so simple.


For More Information On Mustang SVE Alternator Warranties, Please Visit : Musang SVE Alternator Warranty Page

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