Ecodiesel Voltage Fluctuation

[J-Cooz]

Does anyone elses Ecodiesel Voltage fluctuate while driving? If I accelerate it drops to 12.6V or so and if I let off it goes up to 14.5 or so. At cruise on the highway it's around 13V.

I had the battery replaced last year under warranty, it did this before and after.

From reading online some say it's normal and it's the smart alternator.

Can anybody check theirs while driving?

 

[tom318]

Does anyone elses Ecodiesel Voltage fluctuate while driving? If I accelerate it drops to 12.6V or so and if I let off it goes up to 14.5 or so. At cruise on the highway it's around 13V.

I had the battery replaced last year under warranty, it did this before and after.

From reading online some say it's normal and it's the smart alternator.

Can anybody check theirs while driving?

Went out for for a quick drive. 75 out and ac set to auto at 72. Headlights and fogs on. Windows down with no music. No other features on.
Cold start idle with auto ac - 12.8v
Shift to drive at 0mph - 13.8v
Hard acceleration once warm- 13.0
50-60mph with no cruise - 13.0-14.5 depending on hills and throttle.
cruise at 60mph - 13.0 - 14.0.
mine never dipped below 13 and never above 14.5.
never replaced battery and about 27k miles on the truck.

 

[blankcanvas]

Does anyone elses Ecodiesel Voltage fluctuate while driving? If I accelerate it drops to 12.6V or so and if I let off it goes up to 14.5 or so. At cruise on the highway it's around 13V.

I had the battery replaced last year under warranty, it did this before and after.

From reading online some say it's normal and it's the smart alternator.

Can anybody check theirs while driving?

Ok I only have a couple hundred miles on mine but saw your post so went and added some more… you know in the name of science Teehee and nope
Yes I’m aware that my response is pretty irrelevant given it’s a week old truck but I gives it anyways

 

[J-Cooz]

Went out for for a quick drive. 75 out and ac set to auto at 72. Headlights and fogs on. Windows down with no music. No other features on.
Cold start idle with auto ac - 12.8v
Shift to drive at 0mph - 13.8v
Hard acceleration once warm- 13.0
50-60mph with no cruise - 13.0-14.5 depending on hills and throttle.
cruise at 60mph - 13.0 - 14.0.
mine never dipped below 13 and never above 14.5.
never replaced battery and about 27k miles on the truck.

Thank you. So it sounds normal then. Just weird to see the voltage fluctuate so much

 

[Sascwatch]

My truck used to do the same, it seemed like it would use the alternator for some added engine braking when going down hills or coasting. While accelerating it would reduce the output (I’d assume for economy).

And then I had a software update done along with having all of the ground connections under the hood cleaned down to bare metal due to dead battery issues. After that the alternator seems to output much higher voltage at all times, the voltage is typically 14+ while running even on long 15+ hour drives.

 

[NorthStar]

Thank you. So it sounds normal then. Just weird to see the voltage fluctuate so much

You think our Ecodiesels fluctuate, you should see the eTorques…they’re all over the place on voltage readout but is normal. Unless they drop off like a few guys have encountered and then it’s Service Department time.

 

[Dragonmaster13]

With 12.7v being a full charge on a battery, anything higher is ok. Mine fluctuates just like yours.

 

[mrfreon]

Here's a copy & paste from WXman. He answered this question several months ago....

The alternator isn't charging the battery 100% of the time. It's designed to maintain a particular level of charge, depending on driving conditions, so that the vehicle has the power it needs while not consuming extra fuel to spin the alternator.

 

[Aseras]

It's pretty well known in the battery threads that FCA BMS implementation is heavily flawed to boost MPG numbers for CAFE readings to the point of running batteries dead on purpose to gain fractions of a percent in mileage.

If you want proof, simply unplug the lead going to the BMS sensor on the negative terminal of the battery and then check your voltages.

 

[Chris3058]

Mine does the same thing.

 

[J-Cooz]

Ok good to know. Sounds normal then. It's just weird to see it fluctuate so much. I have to imagine that's pretty hard on the battery especially in extreme temps.

Sent from my SM-G781W using Tapatalk

 

[Chris3058]

I was thinking the same thing as you…

 

[Lexaria]

I’ve got the same issue. RAM Rebel 3.0 V6 EcoDiesel. While driving charging voltage always fluctuates and drops down to 12.5 Volts.

I would never trace voltage meter data but My DVR was always turning off and on. That’s why I started looking at battery voltage display.


Any ideas? Have somebody managed what to do with that issue?

 

[J-Cooz]

I’ve got the same issue. RAM Rebel 3.0 V6 EcoDiesel. While driving charging voltage always fluctuates and drops down to 12.5 Volts.

I would never trace voltage meter data but My DVR was always turning off and on. That’s why I started looking at battery voltage display.
View attachment 138280

Any ideas? Have somebody managed what to do with that issue?

I had my truck reflashed and the battery monitor replaced. It fixed my no remote starting.

The voltage will fluctuate still as it's part of the intelligent charging system.

Sent from my SM-G781W using Tapatalk

 

[Rebelguy2020]

My 2020 Rebel diesel with 61,000km does the same thing, I had mentioned it to the dealer when new and they confirmed it was normal.
So far this truck has been extremely good to me, only the key fob batteries were changed.

 

[J-Cooz]

Yep. My understanding is that when you're under heavy load it basically stops charging and when decelerating or light load it will charge. This helps reduce parasitic drag on the engine.

Sent from my SM-G781W using Tapatalk

 

[Chris3058]

Does anyone elses Ecodiesel Voltage fluctuate while driving? If I accelerate it drops to 12.6V or so and if I let off it goes up to 14.5 or so. At cruise on the highway it's around 13V.

I had the battery replaced last year under warranty, it did this before and after.

From reading online some say it's normal and it's the smart alternator.

Can anybody check theirs while driving?

Mine does the same. Always has. Weird as hell.