Battery drain issues

[tdeverjr]

I have a 2025 Longhorn with just over 3000 miles on it. Went out to start it one morning and battery was completely dead. Bring to local dealer can’t find anything wrong, 2 weeks later same issue. Have it at a the shop I bought it from now hearing the same story that everything seems fine. Not sure what to do

 

[vtcats]

Yes. In my case it was a less than perfect connection at the driver side fender main ground, next to the hood hinge.
I cleaned it really good and applied conductive silver grease to keep it from getting oxidized again, knock on wood, been good since Jan 20 2022.

How did you find it? I would imagine there a tons of places with ground wires throughout the truck

 

[kapinallinen2]

How did you find it? I would imagine there a tons of places with ground wires throughout the truck

It is the main grounding point from the battery to the truck, so checked it first and got lucky.
As far as troubleshooting it, I used a multi-meter from the negative battery post to the ground stud and measured 0.1 volt drop between the two points.
Also remembered seeing the TSB about a poor connection possibly causing issues.
Yes, there are around 30 or so ground connections in all.

 

[vtcats]

It is the main grounding point from the battery to the truck, so checked it first and got lucky.
As far as troubleshooting it, I used a multi-meter from the negative battery post to the ground stud and measured 0.1 volt drop between the two points.
Also remembered seeing the TSB about a poor connection possibly causing issues.
Yes, there are around 30 or so ground connections in all.

Thanks, I also have a clamp meter I used on my boat to track/mesure DC amp draws for a multitude of things. I wish we had a schmatic and/or pictures of all those ground connections on this truck. Before my 24 limited went in for a new engine (yes, ugh with only 7100 miles), I noticed the battery was just below 12 volts. I keep track of its voltage since new and it has never been below 12.3 (that was after 3 weeks of sitting this past summer). So because I’m sure the mechanic will only focus on the engine, I’m kind of expecting something like what you describe after getting it back next week…I’ve got a jump pack regardless.

 

[kapinallinen2]

I wish we had a schmatic and/or pictures of all those ground connections on this truck.

This is on my 2019. You can get model year specific by subscribing to Alldatadiy for not much money.

 

[kapinallinen2]

These do not crop and retain resolution all that well when posting here but should give you an idea of what info is available.

 

[vtcats]

These do not crop and retain resolution all that well when posting here but should give you an idea of what info is available.
View attachment 194308

Thank you!!!!

 

[Ramboxfan]

We just bought a 2025 RAM 1500 Limited, 600miles. Same problem with battery dying. At dealer since Thursday PM. They were able to tell there is a drain, but can't find it, working with engineers/manufacturer. Did any of you get resolution to your battery draining? Or was it a problem with charging system?

 

[Ramboxfan]

We just bought a 2025 RAM 1500 Limited, 600miles. Same problem with battery dying. At dealer since Thursday PM. They were able to tell there is a drain, but can't find it, working with engineers/manufacturer. Did any of you get resolution to your battery draining? Or was it a problem with charging system?

 

[MRP03]

See this video I took from my 2025 Big horn Hurricane engne, after I disconnected the batteries and then re-connected. You hear moving electronic parts, then a whining sound until I pull the neg battery lead. You may have to turn up the volume. I'll try to get a better video with louder sound. Any ideas ?

VID_20250125_153100671.mp4

drive.google.com

 

[htran007]

So there’s no solution yet. I’m having same problem too. I would charge it to full, start no problem. If I jumpstart, it runs fine but turn it off and back on, it struggle to crank on.

 

[Tflan]

This same scenario has happened to my 2025 Rebel again this morning for the 2nd time in less than 1100 miles.

 

[gskowronek]

This same scenario has happened to my 2025 Rebel again this morning for the 2nd time in less than 1100 miles.

Post in thread '2025 Ram 1500 Current Owners - Discussion, Feedback, and Problems'

Feb 5, 2025

Hello. I just purchased a 2025 RHO. Drove home from the Dealer, 10 miles no issue. My wife drove it another 100 miles or so the next day to an event and back with no issues. The next day I drove it 55 miles to work with almost no issues. Getting on thr freeway at 4500 RPM's I got a cruise control error, an automatic emergency breaking issue, and maybe a few other ones. As soon as I pulled into the parking lot, I got a check engine light, all the same messages on the dash, and it was stuck in gear. Would not shift up or down.

When I left that day, the check engine light was still one...

• itsmekylep

 

[RamLtd19]

We just bought a 2025 RAM 1500 Limited, 600miles. Same problem with battery dying. At dealer since Thursday PM. They were able to tell there is a drain, but can't find it, working with engineers/manufacturer. Did any of you get resolution to your battery draining? Or was it a problem with charging system?

Check out this thread:

https://5thgenrams.com/community/direct-messages/same-issue-with-my-2019-ram-1500.171757/#convMessage-301169

 

[Tflan]

Check out this thread:

https://5thgenrams.com/community/direct-messages/same-issue-with-my-2019-ram-1500.171757/#convMessage-301169

That link is a dead end for me.

 

[sundayplace]

Check out this thread:

https://5thgenrams.com/community/direct-messages/same-issue-with-my-2019-ram-1500.171757/#convMessage-301169

That link is dead end for me too.

 

[sundayplace]

I have a 2025 RAM 1500 and am having battery drain issues as well. Today, on cold start, the voltage reading system showed below 8 volts, but once engine started alternator recharged it to 14+ volts. Took it to the dealer, they connected their computer and said there are no issues. Once it warms up a little, I plan on pulling fuses to try to diagnose drain issue. I appreciate all the insights shared to date.

 

[kapinallinen2]

I plan on pulling fuses to try to diagnose drain issue.

That may or may not work, it could be possible that the modules might not shut down when the polling comes up incomplete. Faintly remember reading that somewhere.

 

[RamLtd19]

That link is a dead end for me.

Been meaning to post on this as I think I found a fix. RF hub wasn’t the issue. I replaced the can bus star connector located behind the panel to the left of the steering wheel. ~$70 fix you can do yourself. Just pull the pins out of the old one, one by one, and place into the new one. Haven’t had battery drain or electrical issues for 2 months now.
Had a daily parasitic battery drain. Dealership would test then recommend I replace a module. Replaced the rf hub, still drained, replaced the radio/screen, still draining, then they recommended a complete wiring harness replacement, which I didn’t do. My dash warning lights and cluster began lighting up like a Xmas tree, truck randomly responded to the key fob, and still draining the battery. When I tested the battery the source of draw was inconsistent. This led me to believe it’s a network connection issue and not specific modules causing the problem. Found a couple videos online that hinted at the same thing and from various Stellantis brands so I figured for $70 it was worth a try.

Before you go to the dealership,1.) watch the videos below, 2.) buy a cheap OBD reader and see what codes it throws (wish I did this sooner). If it has lots of lost comms codes I bet your looking at a network issue and not a module failing issue. Super easy to use and pairs to an app on your phone (links below). Either way you have documentation to push them to look into it. Mine was throwing tons of these codes when the dealership initially scanned it and they ignored them. I asked for the reports after their suggested module fixes did nothing, well other than costing me $1k, time, frustration, etc. , and began diagnosing myself. I’m not a mechanic, just someone who hates being taken advantage of. For $160 on the reader and replacement part you break even for what the dealership charges for one “diagnosis” fee.

Dealerships are not looking to diagnose a cure. They recommend bandaids for problems for the exact reason you stated…replacement of modules to make a ton of money on parts and labor. IMO, cars are engineered this way to ensure failures and retain incoming revenue from you after the sale.

Star Connector Can bus: 2017-2025 Mopar Connector Can Buss 68321746AA | Mopar Online Parts

OBD reader: Amazon.com