Battery Voltage on 2020 Challenger Hellcat

scottm0690 said:

Hello all, I haven't been able to get a solid answer from Dodge on this and they want me to spend over $100 to test/validate my alternator. I am currently showing a 13.8 Battery Voltage on my car. No matter how long i drive, or accelerate it never goes up, but when i was driving on a long trip, it went from 13.9-13.8. Never went higher than 13.9 and I am concerned if there is an alternator problem. Is this still a good voltage? Is this an indication that the alternator is going? Any mechanical expertise would be appreciated. Thanks.

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Battery voltage when the engine is running can vary. The alternator output is varied depending upon the electrical needs of the car.

From what I recall from my Hellcat (and a car before the Hellcat that had a battery voltage gauge) and more recently my 2020 Scat Pack is is in cold weather the battery voltage was in the 14.2V to 14.4V but in the summer a tenth or two less.

A cold battery can require more topping up. And the lights and seat and steering wheel heater and the A/C and cabin vent fan all require electricity.

In the case of your car 13.8V is all the car needs electricity wise.

I did have a car which after some run time (approx. 30 minutes) started showing the battery voltage dropping. I watched it for a bit as it went down to under 13V and I suspected the alternator was bad and headed to the dealer. By the time I got there the battery voltage was just above 12V. Left the car and the tech confirmed my suspicion. The alternator was bad.