2025 RAM 1500 Parasitic Battery Drain

[sundayplace]

I bought my 2025 RAM 1500 end of August 2024. Several electrical issues.
1. The battery has a parasitic drain (11.4 volts with engine off; 13.8 volts engine running). Haven't started diagnosing yet.
2. At ~1700 miles, three things happened within a few days (1) Notification flashed a few times saying "AEBS (automatic emergency brake system) is deactivated", (2) on Uconnect screen this notification appeared "Uconnect Box Requires Service. Please visit authorized dealer." and (3) front sensors spuriously activated with no objects in its path.

Dealer didn't seem to want to diagnose parasitic drain - said battery is fine. They are replacing front sensors. No answer for the AEBS and Uconnect Box Requires Service notifications.

Anyone else have these issues? Any insights on the issues would be greatly appreciated!

 

[sundayplace]

I bought my 2025 RAM 1500 end of August 2024. Several electrical issues.
1. The battery has a parasitic drain (11.4 volts with engine off; 13.8 volts engine running). Haven't started diagnosing yet.
2. At ~1700 miles, three things happened within a few days (1) Notification flashed a few times saying "AEBS (automatic emergency brake system) is deactivated", (2) on Uconnect screen this notification appeared "Uconnect Box Requires Service. Please visit authorized dealer." and (3) front sensors spuriously activated with no objects in its path.

Dealer didn't seem to want to diagnose parasitic drain - said battery is fine. They are replacing front sensors. No answer for the AEBS and Uconnect Box Requires Service notifications.

Anyone else have these issues? Any insights on the issues would be greatly appreciated!

More information on the parasitic battery drain...

When the Auto engine turn off button is off (normal status) and the engine shuts off, the battery voltage drops to 11 volts. Could the parasitic drain be because of the auto engine shutoff system?

Any insights would be appreciated!

 

[Kilroy]

ALL newer vehicles will have "some" parasitic battery loss, just the nature of the the newer technology. My understanding and experience, once battery capacity drops below a specific voltage, those systems will shut down preventing a dead battery state. But in all fairness that happening is pretty much non-existent if the truck is driven occasionally. If not a battery tender is required.

 

[Kilroy]

I bought my 2025 RAM 1500 end of August 2024. Several electrical issues.
1. The battery has a parasitic drain (11.4 volts with engine off; 13.8 volts engine running). Haven't started diagnosing yet.
2. At ~1700 miles, three things happened within a few days (1) Notification flashed a few times saying "AEBS (automatic emergency brake system) is deactivated", (2) on Uconnect screen this notification appeared "Uconnect Box Requires Service. Please visit authorized dealer." and (3) front sensors spuriously activated with no objects in its path.

Dealer didn't seem to want to diagnose parasitic drain - said battery is fine. They are replacing front sensors. No answer for the AEBS and Uconnect Box Requires Service notifications.

Anyone else have these issues? Any insights on the issues would be greatly appreciated!

Have you had the battery tested? You could have an issue in the electrical system, chargers plugged into USB ports, any additional accessories connected other than stock?

 

[sundayplace]

Have you had the battery tested? You could have an issue in the electrical system, chargers plugged into USB ports, any additional accessories connected other than stock?

Thanks, Kilroy. The service tech "tested" the battery with a 3-hour "parasitic draw test." Result as stated on the invoice include "Verified customer complaint while driving and auto start stop engages voltage will drop down to 11 volts. This is due to MGU not charging vehicle as engine is not running. While driving MGU charging battery as designed. Customer has checked battery voltage while in run position without running engine. while in shop performed parasitic draw test. No draw at this time within draw test spec of 0.030amp. Tested battery on RO 216226 and battery passed. Unable to duplicate draw at this time. Vehicle operating as designed at this time."

I'm not sure what that means. Any insights would be appreicated.

 

[sundayplace]

Have you had the battery tested? You could have an issue in the electrical system, chargers plugged into USB ports, any additional accessories connected other than stock?

No chargers plugged into USB ports or other accessories.

 

[sundayplace]

ALL newer vehicles will have "some" parasitic battery loss, just the nature of the the newer technology. My understanding and experience, once battery capacity drops below a specific voltage, those systems will shut down preventing a dead battery state. But in all fairness that happening is pretty much non-existent if the truck is driven occasionally. If not a battery tender is required.

Thank you, Kilroy. I plan to take the truck with a trailer on the road and am a bit concerned about the parasitic drain creating a shorter battery life. I'd hate to loose the battery in the middle of the woods without service. So, I'm not sure how best to use a battery tender for that type of use.

 

[MarkTTU]

Thanks, Kilroy. The service tech "tested" the battery with a 3-hour "parasitic draw test." Result as stated on the invoice include "Verified customer complaint while driving and auto start stop engages voltage will drop down to 11 volts. This is due to MGU not charging vehicle as engine is not running. While driving MGU charging battery as designed. Customer has checked battery voltage while in run position without running engine. while in shop performed parasitic draw test. No draw at this time within draw test spec of 0.030amp. Tested battery on RO 216226 and battery passed. Unable to duplicate draw at this time. Vehicle operating as designed at this time."

I'm not sure what that means. Any insights would be appreicated.

A “12v” battery in any car will read somewhere between about 11.5 and 12.5 when it’s good and not being charged. 11v is a little low, but not enough to determine you have a bad battery. 13-14v while the engine is running is normal, the alternator runs at a higher voltage than the battery voltage (causing the battery to charge).

Measuring parasitic drain can’t be done by simply observing the battery voltage. To measure drain (parasitic or otherwise) you need to measure amps being drawn out of the battery. Amps are how you measure how much electricity is flowing. You can think of volts like water pressure and amps like water volume.

The service tech measured amps while the vehicle was off (ie parasitic drain) and, while he didn’t note what his measurement was, he did note that the drain was less than the 0.030A the vehicle engineers say would be normal. That’s a tiny amount of power being drawn out of a car battery.

If it helps put it into perspective a typical new truck battery will have around an 80Ah (amp hour) rating. So at 0.03A the battery should last around 2,600 hours which is more than 100 days. At that point the battery would be flat and not able to supply enough amps to even sustain the 0.03A parasitic drain so to still be able to start the truck you can’t let it go anywhere near that long, but a couple of weeks or even a month at that kind of drain rate shouldn’t pose any issues.

 

[kapinallinen2]

Here is an example of a real life parasitic draw. In this video my truck is connected to an external power supply.
Keeps repeating the cycle over and over, the battery stood no chance.

 

[sundayplace]

A “12v” battery in any car will read somewhere between about 11.5 and 12.5 when it’s good and not being charged. 11v is a little low, but not enough to determine you have a bad battery. 13-14v while the engine is running is normal, the alternator runs at a higher voltage than the battery voltage (causing the battery to charge).

Measuring parasitic drain can’t be done by simply observing the battery voltage. To measure drain (parasitic or otherwise) you need to measure amps being drawn out of the battery. Amps are how you measure how much electricity is flowing. You can think of volts like water pressure and amps like water volume.

The service tech measured amps while the vehicle was off (ie parasitic drain) and, while he didn’t note what his measurement was, he did note that the drain was less than the 0.030A the vehicle engineers say would be normal. That’s a tiny amount of power being drawn out of a car battery.

If it helps put it into perspective a typical new truck battery will have around an 80Ah (amp hour) rating. So at 0.03A the battery should last around 2,600 hours which is more than 100 days. At that point the battery would be flat and not able to supply enough amps to even sustain the 0.03A parasitic drain so to still be able to start the truck you can’t let it go anywhere near that long, but a couple of weeks or even a month at that kind of drain rate shouldn’t pose any issues.

Thanks for sharing that information, MarkTTU. It's a brand new truck I bought at the end of August 2024. I assume the 2,600 hours is continuous operation. Service guy said the batteries last on average about 3 years.

 

[sundayplace]

Here is an example of a real life parasitic draw. In this video my truck is connected to an external power supply.
Keeps repeating the cycle over and over, the battery stood no chance.

kapinallinen2, thanks for sharing your video. It's a bit crazy that the electronics can draw on the battery overnight every day. I'm going to hook up a volt meter to measure amps and start pulling fuses to try to locate the most offensive electronic systems.

 

[MarkTTU]

Thanks for sharing that information, MarkTTU. It's a brand new truck I bought at the end of August 2024. I assume the 2,600 hours is continuous operation. Service guy said the batteries last on average about 3 years.

Yes, that 2,600 hour number would be if the battery was never charged. Any time the truck is running the battery should be charging so really you'd need to go 2,600 hours without starting the truck.

Worth mentioning I don't know what the battery is in the 2025 Ram so that's just a rough guess type of number, but if the parasitic draw is as low as the tech measured then your battery should be fine with you not starting the truck for at least several weeks with no concern.

 

[RamLtd19]

Check out this thread for possible answer. Worked for me and at least one other person.

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

 

[MarkTTU]

Check out this thread for possible answer. Worked for me and at least one other person.

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

Links to your DMs don't work for the rest of us... DMs are private communication.

 

[RamLtd19]

Links to your DMs don't work for the rest of us... DMs are private communication.

Apologies…

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 6 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

 

[sundayplace]

Apologies…

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 6 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

Thanks for the tips, RamLtd19. I'll look to see whether I have the same configuration as my truck is a 2025.

 

[3rdRamSad]

I have a 2025 1500 Laramie. I have had the truck since Nov 17, it had been at the dealer for service on this issue over 30 days up until 2/20. They have replaced the main battery, the auto start stop battery and a turbo waterpump, all traced to parasitic drains. In each case the truck had to be left 5 days or more. The battery was so low the truck could not be started with a jump box and was towed in. The last event was 2/4-2/10; the truck was left in my garage without starting. It once again was very dead. The dealer recharged the battery and ran repeated parasitic drain tests and could not replicate it. I picked up the truck on 2/20, the STAR group's conclusion was that there is something environmental (LED lights, motion detectors, TPMS, key fobs whether RAM or others, electric motors, flashing lights, etc.) causing the truck to wake up. Since picked up I have been pretty busy, but have tested voltage and had the dash battery voltage displayed. Have not seen voltage under 12v when not running, not under 13v when running. I did buy a faraday bag for my spare fob and keep my active one more than 30' away. I have turned off some lights but will reintroduce over time. I will get a chance at some point to let it sit, so far 2 days is longest. I have checked with a couple electrical engineers, cars have to be shielded against interference. My Subaru is parked in the same garage and left without running for several days with no issues. I have approached Stellantis for resolution.

 

[3rdRamSad]

I heard from Stellantis corporate, Mike MacDonald today. Very fair resolution and compensation. I hope problem resolves.

 

[Willwork4truck]

I briefly read the post from 3rdRamSad and noticed that after the dealer replaced the battery it was stone dead again. I wouldn't trust that replacement battery now.
Hope it gets resolved, hard to see how your key storage or other items etc is doing this in 5 days. Imagine leaving the truck in airport parking then comingback to it…
Yes the computer and screens get woken up but so many other late model brands of vehicles don't have the problem. Too many other 2025 RAMs have these issues…

 

[Bsjoiner]

I have a 2025 1500 Laramie. I have had the truck since Nov 17, it had been at the dealer for service on this issue over 30 days up until 2/20. They have replaced the main battery, the auto start stop battery and a turbo waterpump, all traced to parasitic drains. In each case the truck had to be left 5 days or more. The battery was so low the truck could not be started with a jump box and was towed in. The last event was 2/4-2/10; the truck was left in my garage without starting. It once again was very dead. The dealer recharged the battery and ran repeated parasitic drain tests and could not replicate it. I picked up the truck on 2/20, the STAR group's conclusion was that there is something environmental (LED lights, motion detectors, TPMS, key fobs whether RAM or others, electric motors, flashing lights, etc.) causing the truck to wake up. Since picked up I have been pretty busy, but have tested voltage and had the dash battery voltage displayed. Have not seen voltage under 12v when not running, not under 13v when running. I did buy a faraday bag for my spare fob and keep my active one more than 30' away. I have turned off some lights but will reintroduce over time. I will get a chance at some point to let it sit, so far 2 days is longest. I have checked with a couple electrical engineers, cars have to be shielded against interference. My Subaru is parked in the same garage and left without running for several days with no issues. I have approached Stellantis for resolution.

I have an almost exact same situation. They have ordered me a new truck. I have owned my truck for about 6 months (Tungsten) and it has been at the dealer for almost half of that time. I know longer trust this truck to start and it has left me stranded more than once. Hopefully new one is not a problem. Stellantis is supposed to cover the cost gap with the deal so it should be zero out of pocket for me.