Alternator voltage question.

[davekeller79]

When I first got my 2019 Limited (5.7 no etorque) the alternator voltage would display just over 14 for the first few miles, then drop off to 13 . Something. I und this is due to it recharging your battery from the engine start, then just maintaining at the lower voltage so the alternator has less drag on the motor.

I noticed recently that it never drops anymore. Even on hours long drives.

Is this something I should be concerned about?

Thanks.

 

[bigdodge]

When I first got my 2019 Limited (5.7 no etorque) the alternator voltage would display just over 14 for the first few miles, then drop off to 13 . Something. I und this is due to it recharging your battery from the engine start, then just maintaining at the lower voltage so the alternator has less drag on the motor.

I noticed recently that it never drops anymore. Even on hours long drives.

Is this something I should be concerned about?

Thanks.

battery getting old?

 

[ic3man5]

ECU controls the voltage, its based off of temperature and if it thinks the battery is low. Top table is the "normal" voltage and the bottom table is the "low" voltage.



My battery only lasted 2 years before I had to replace it. Everstart Premium brand from Walmart is one of the best battery replacements for the best price. I couldn't even do a crank test on the everstart battery because the voltage didn't drop enough on crank/start for it to detect it. My old battery still showed good CCA but the voltage dip on crank was enough for the ECU to hate it.

I used this:

https://www.amazon.com/gp/product/B08MPXGSGN/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[davekeller79]

ECU controls the voltage, its based off of temperature and if it thinks the battery is low. Top table is the "normal" voltage and the bottom table is the "low" voltage.
View attachment 156785


My battery only lasted 2 years before I had to replace it. Everstart Premium brand from Walmart is one of the best battery replacements for the best price. I couldn't even do a crank test on the everstart battery because the voltage didn't drop enough on crank/start for it to detect it. My old battery still showed good CCA but the voltage dip on crank was enough for the ECU to hate it.

I used this:

https://www.amazon.com/gp/product/B08MPXGSGN/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Thank you so much for such a an informative reply.

 

[davekeller79]

Since you seem to be very clued in, one day out of nowhere, I went to start my truck and the battery was dead as a doornail. For no apparent reason. I got a jump start and have t had an issue since. Any thoughts?

 

[ic3man5]

Since you seem to be very clued in, one day out of nowhere, I went to start my truck and the battery was dead as a doornail. For no apparent reason. I got a jump start and have t had an issue since. Any thoughts?

The computers in the truck should be smart enough to shut down anything that will kill the battery completely. Maybe it's possible you left it in accessory or run mode, that would probably kill it.

Chevy Silverados used to have a bug that would make the radio never shut off after a timeout if you opened the passenger door to remove the key instead of the driver door. That was a fun one to figure out.