2022 Ram Diesel Batteries

[SSchang]

So my 2022 3500 Ram/Cummins with 170 miles has had a problem where it won't crank the engine if it sits for 2-3 days. It's at the dealer, they couldn't find any parasitic loads, the driver side battery is fully charged and the passenger side battery was severely discharged.

Aren't the batteries wired together so they charge and drain together? The dealer is telling me the driver side battery is to start the truck, and the passenger side battery is for everything else. So one can be charged and the other discharged.

Then why if the passenger side battery was drained wouldn't the truck start if it's not for starting the truck?

Can anyone help me understand how this works?

 

[lpennock]

Bad cell in the passenger side battery. The cross over cable should keep both batteries at same state of charge.

PS dealer is full of it. Both batteries are used for everything; however, some circuits are directly connect to one or the other.

 

[kthaxton]

Yeah, that is absurd. The two batteries are connected together and function as one large battery. It would seem it would have to be a bad cell as mentioned above, or a connection issue between the two. If it is a bad cell, the bad battery will drag the good one down with it eventually.

I am baffled by the nonsense that sometimes comes from dealers (in practically any field) where they should know better.

 

[SSchang]

So late breaking information form the dealer on this:

What they are telling me is they fully charged and load tested both batteries. The driver side is in perfect condition, and the passenger side is "within specifications", so they can't replace it under warranty.

Oh, and a detail I left out - I did install Amp power running boards on the truck, and tied them into the number 1 Aux switch. The dealer is leaning toward the steps are what drained the passenger side battery.

 

[AH64ID]

So late breaking information form the dealer on this:

What they are telling me is they fully charged and load tested both batteries. The driver side is in perfect condition, and the passenger side is "within specifications", so they can't replace it under warranty.

Oh, and a detail I left out - I did install Amp power running boards on the truck, and tied them into the number 1 Aux switch. The dealer is leaning toward the steps are what drained the passenger side battery.

If you have the aux switch setup to stay on with the ignition off then yes that is likely true. There is a relay that the aux switch keeps open and that will drain the batteries over time. I would find a different constant power source underhood.

If my 18 sits for more than 2-3 days I put it on a NOCO Genius 5 tender, but it will still start if it sits for MUCH longer.

 

[kthaxton]

Oh, and a detail I left out - I did install Amp power running boards on the truck, and tied them into the number 1 Aux switch. The dealer is leaning toward the steps are what drained the passenger side battery.

Since the batteries are tied together....it shouldn't drain one any more than the other....assuming both batteries are in good condition. Strange deal with the dealer...but it is what it is.

 

[BigPapa]

I would run from that dealer/Service Manager/Writer/Service Department if that’s what they told you. I wager the crossover cable isn’t connected.

 

[JR]

Did they change the location of the Aux switch connections under the hood? They used to be on the drivers side, which in turn is tied into the drivers side battery through the pdc. Ask them how that is killing the passenger side battery only. Then ask them if they are load testing the batteries with the crossover cable disconnected.

 

[Cummins12V98]

You need a different Dealer!!!

 

[TMyers]

I don't know how the batteries are connected but as we entered winter, my batteries wouldn't start my truck on a cold morning. No problem, I got my wife's SUV and cables out and tried to jump the truck off hooking the cables to the passenger side battery. Didn't help at all. I switched the cables to the driver's side and my truck started right up. I'm confident that I had good connections on both attempts.

Two Napa/East Penn AGM batteries and $400 later, all is well.

 

[Timd32]

Wonder what the draw test is actually showing for a draw total.

Noting posted for a '22 yet but here is some '21 info just for reference.

With so few miles this thing does sit a lot of its life so far.

If it was at the lower end of the charge cycle on a short run, I could see this happening on a brand new unit that sits for a few days. You should be able to calculate out the draw on the system at different charge rates.

And who knows if something failed to go to sleep properly and it had a higher draw at time of issue, that would be hard to catch.

Hope you get it sorted.

We find alot of these PDF's are also in the owners manual at times...

 

[AH64ID]

I don't know how the batteries are connected but as we entered winter, my batteries wouldn't start my truck on a cold morning. No problem, I got my wife's SUV and cables out and tried to jump the truck off hooking the cables to the passenger side battery. Didn't help at all. I switched the cables to the driver's side and my truck started right up. I'm confident that I had good connections on both attempts.

Two Napa/East Penn AGM batteries and $400 later, all is well.

You could have a bad crossover cable.

 

[GroundSquirrel]

Not to hijack this thread but has anyone else had issues with batteries in their 4th gen? My OEM set crapped out about 60k, and I just had to replace the replacements about 104K. I replaced the bats only old 3rd gen at 180K and I only did that for reassurance.

 

[lpennock]

Mileage means nothing talking battery life. How many months did each last?

 

[BigPapa]

We have several ‘17 model 3500 pickups and 4500 C&C’s in our fleet and we’ve found we’re having to replace the batteries much more often than anticipated. I keep six in stock at all times.

 

[Wiredawg]

My 5500 had one battery develop a bad cell. Too many short trips and lots of electronics, seat auto moving into position, lights all on, might turn them off auto. Mine made it a little over 4 years... replaced with two Crafstman AGMs for $400. Now I place on battery maintainer everyday.

 

[gsbrockman]

Mileage means nothing talking battery life. How many months did each last?

Point of reference on mine.....

• Purchased new April 23, 2018
• Batteries replaced May 11, 2021
• 333,970 miles
• 5,830 drive hours

 

[lpennock]

3-4 years about normal these years except for us desert rats where 2-3 is more normal.

 

[CToney]

Since I don’t drive my truck much adding a battery tender probably isn’t a bad idea. I’ll put a tender on equipment in my storage shed over the winter once to keep them charged. Most of them have battery shutoffs.

 

[Timd32]

Good thing a bad cell is coming back if the charge did not burn out any shorts between the plates. So that will kinda solve it's self not the best solution if it's a bad cell that always sucks to have to go back and forth.

But the dealer level charger reads like it's pretty neat, I don't think the skill level would matter with that part. It probably removes most human error the way it works.

Lack of mileage = sitting, is what I was thinking. Time sitting and just having the truck draw down the cells is super common if something did not properly go to sleep. Key fobs kept in the truck have caused some issues.

In some other posts this truck was in transit end of Oct, maybe look at the offical build date and work from that was it sitting waiting for something in a lot, or just use that Oct date.

The "shipping mode" was discussed last week a bit, I forget exactly what that mode is doing, but if it's super limited draw it could drain off of one side while sitting very long.

2.5 months since shipping and 170 miles kinda leads me to say it's been sitting a while and lots of smaller trips. Which is no problem just might need a NOCO set up to help things along.

Add in the inadvertent power step draw, possible bad timing on some short runs, low charge event, could have always been miss matched cells to start with.

Fresh charge on all things could be all this thing needs.

The actual draw can be calculated out from the set of batteries. It's not a perfect calculation at times folks have tried tests with home grown set ups to test out stuff for battery capacity. In this case the draws are so small, it will be a super long run time.

If able maybe pick out some good tunes, sit back and put a few miles on this thing and get thru the break in period for the drive train parts. Sounds like a super nice truck. Enjoy.