Starting amp draw?

[gfl22]

The only thing im skeptical of is when I start my 6.4 , the amp gauge goes to the right roughly 1/4 down, then eventually works its way back up to normal, if driven a couple hours
This happens with a brand new fully charged agm battery (replaced it hoping that was it) , original would be dead after a couple weeks in the garage.

This is my 5th Ram, and its the only one thats done this.

Am I crazy to think this isn't right and will likely get worse over time?

 

[2003F350]

My '17 acts that way for a bit as well, but by the time I get to work everything is fine. Work is only a 30 minute drive. Original battery (knock on wood).

 

[62Blazer]

Not sure what you are saying is really unusual or not. So saying the gauge goes to the right, or increases, after starting is pretty normal as the starter pulls a lot of amps and the gauge is indicating the alternator is supplying a higher power level to replenish the battery. As you drive the battery is getting replenished and requires less power.
In regards to the comment about the previous battery going dead after sitting for a couple weeks, if the battery was simply getting old that is not uncommon. Newer vehicles have a small but continuous draw on the battery even when turned off, and an old and weak battery can very well go dead after sitting for a couple of weeks because of this. Point being is I'm not sure what you describe as a possibly current issue has anything to do with the previous issue of the battery going dead.

 

[gfl22]

well , it just seems that this one goes further to the right than everyone else's and even after a full charge of the battery.

side question, you on teryx site too?

 

[crash68]

original would be dead after a couple weeks in the garage.

If the vehicle is going to be parked weeks at a time, get yourself a battery maintainer. Allow the battery to discharge consistently low will shorten the battery life. Many on this forum use ones from NOCO.

The ECM in these vehicles control the alternator charging the battery, they use information from the IBS which is on the negative battery terminal.
The dash gauges are in no way an accurate "gauge" but more of a reference point. If the gauge does something different then start looking for a problem.
You can use the something like the Torque App or AlfaOBD to read the actual battery and ECM voltage.

 

[RamDiver]

I'd like to get a set of these for the USB feature and a digital voltage indicator. Hard to beat at $20 for the two units.

Not helpful for the current draw but a great method to confirm the float voltage after the truck has been sitting unused. If you see anything much below 12.5VDC, the trickle charger/battery maintainer is definitely indicated.

https://www.amazon.com/gp/product/B098KD2G8F/ref=ox_sc_act_title_2?smid=A36QP4GB26KF30&th=1


.

 

[Travelin Ram]

It’s a voltmeter, not an amp gauge.

And as noted above, the PCM charges as it sees fit. It’s not just a simple alternator with a voltage regulator like days of old.

 

[turkeybird56]

It’s a voltmeter, not an amp gauge.

And as noted above, the PCM charges as it sees fit. It’s not just a simple alternator with a voltage regulator like days of old.

Yup, but sometimes I miss the old, was just way easier to take care of.

My battery (OEM 4 1/2 years old), was getting weak (showed 12.02 V at cold rest, verified with a Multi Meter, not truck lie-o-meter, but the truck meter is close), on MY 19, so I went and got a Duralast Platinum put in. After starting, the system will charge up to 14.9 volts, and then after a period go done to 14.8/7. Usually not get below 14.7 as all my trips are just quick jaunts to town, not long highway miles. The next time truck in at Dealer, will for giggles have the system checked and also the IBS checked, just in case.

 

[RamDiver]

It’s a voltmeter, not an amp gauge.

Not helpful for the current draw but a great method to confirm the float voltage after the truck has been sitting unused. If you see anything much below 12.5VDC, the trickle charger/battery maintainer is definitely indicated.
.

As previously indicated, these devices are still helpful to monitor battery float voltage.

This could prove useful for those that don't drive their vehicles daily and also be useful as an advanced indicator to start using a charger before continuing to abuse the battery.

YMMV
.

 

[gfl22]

I've broken.. bought a NOCO onboard maintainer,, now im tossing up ideas on whether to use that , or just a cord to my big battery tender unit that sits close in my garage that i use for camper batteries.

Yes, i'm old school, reading it like a dedicated amp gauge, which is probably why it bothers me. I will try to avoid looking at it.. lol

Thanks for everyone's input.