Repeated dead (dual) batteries, 2020 Ram 3500 diesel

[mcv1]

2020 Ram 3500 Tradesman, 6.7 HO diesel
dual batteries, dual alternator 440-amp, Uconnect 3, 5". No electrical modifications from factory.

On at least 10 occasions my batteries have been dead during first 14 months of ownership (purchased new Dec 2020). Seems very erratic, sometimes dying overnight, but almost always being dead if I have not driven the truck for 5+ days. Typically 100% discharged, such that there are zero interior lights, the key fob won't work, etc. I can successfully jump start (eventually) and the batteries then rapidly recharge with my dual alternators. A RAM dealer in Missoula said they had observed the issue with a Uconnect radio repeatedly attempting some update, but that often the flash for this radio required more than 12 hours!? .... I could not leave the vehicle for that long, so I later scheduled service in Colorado and left the vehicle for 4 days for evaluation and service. I was texted by the service advisor that indeed the radio was causing an intermittent phantom voltage draw (and causing the radio to irritatingly start-up at maximum volume, etc) but that a software update resolved the problem. (This contradicts the paperwork given to me that says they only observed 50-90 milliamp draw, and that I must keep the AUX switch shut off overnight regardless that nothing was plugged into it.) Unfortunately, my batteries were 100% dead after the truck was unused for five days after the service. The AUX switches were off as advised, and nothing plugged into the USB ports. Dual batteries should not 100% deplete in 5 days! The batteries reportedly test good (according to dealer), despite having been 100% discharged at least 6 or 7 times, and highly drained an additional 3 times. When the AUX switches are off (turning off the LED indicator lights), reportedly zero draw is observed on parasitic battery drain tests, perhaps supporting a hypothesis that it is a "computer-related" like UConnect trying to do an update at 3 am or something. But even this shouldn't pull enough amperage to kill dual batteries?

Of course, we have confirmed no interior lights left on. No glove box or underhood light in Tradesman. No added device like phone or GPS or camera. Battery cables seem tight; ground cables seem secure; no visually obvious frayed or damaged wiring based on a quick under-hood exam.

I have read from other RAM/Jeep/Dodge owners that they have had similar issues caused by the Uconnect radio, requiring a full replacement. Others have claimed that RAM got a batch of bad batteries. I have also read that discharging the auto batteries 100% flat at least 6 or 7 times will have done so much permanent damage to them that they will have permanently lost capacity. But dealer claims they are good.

I have been in contact with the service manager and he is willing to take the truck back in for further diagnostics. But I am >100 miles away, and the dealer won't provide an overnight loaner, and RAM has previously refused to pay the full cost of a rental car during previous warranty/recall service attempts. The service manager said he has never heard of a Uconnect radio causing an unusual parasitic draw, although his technician apparently documented it on my truck, based on the text messages I was sent. @RamCares was unable to help other than suggesting I take it to a dealer for evaluation.

I hate to have a brand new vehicle that is entirely untrustworthy. It seems to be a crap shoot as to whether the truck will start if I've left it parked overnight. Always starts perfectly with strong batteries if attempted within 12 hours. Sure, I can purchase a battery tender to solve my problems at home where I can plug it in overnight. But I'd like to be able to have a vehicle reliable enough to go on an overnight trip without being stranded.

Anyone out there been down this road that can offer some advice? Since it remains under warranty, I had hoped that RAM would solve it. However, I suppose I could start pulling fuses to disable the UConnect or something like that? Or I could purchase 2 new batteries out of pocket to see whether that helps. Dealer suggested I may want to pull the IOD fuse (ignition off draw) each time I park where it cannot be plugged into a battery tender. Or is there a more straightforward approach compared to trial and error, when error means being stranded somewhere? Is there an automated "battery isolator" approach that allows one of the dual batteries to be reserved just for starting the truck and prevent it from being drained?

Thanks for any input if you've experienced the problem, or have a suggestion for a battery isolator or other solution.

 

[chopperman1]

Research troubleshooting a parastic draw. Pretty straight forward. Use an ampmeter and start pulling fuses one by one until you locate where the draw is. Being under warranty tho I would just put it in the dealers hands to resolve. Don't let them pull the "batteries are a wear item and not under warranty" when you ask for them to be replaced. They were damaged by an "upstream" component which makes them covered under warranty.

 

[chri5k]

I had a slightly different issue causing both batteries in my 2016 2500 CTD to go completely dead every couple of days. I charged them and put the ammeter on the positive cable. The meter showed a 4.5 amp draw when the truck was supposed to be sleeping. Started unplugging everything from the USB ports. No change. Unplugged the OBDLink MX reader and the draw dropped to 35 - 45 milliamps.

An unexpected draw can kill dual batteries in a day or two. These can be tough to diagnose since it takes time. Many dealers service departments don't want to take the time. When the batteries were dead, I took them out of the truck and fully charged them. Put them back in the truck to start the test. After I found the issue, i retested by allowing the truck to sit unused for two days and monitoring the amperage draw. Initially I checked it every 10 minutes until the draw dropped to about 1 amp. Then I checked every hour. (except when I was sleeping ) These trucks will draw several amps when first shut off. My truck took close to an hour to fully fall asleep. I continued to monitor the current draw and battery charge state for two days to make sure the high current draw did not return. Truck has been fine ever since.

 

[Chris76]

2020 Ram 3500 Tradesman, 6.7 HO diesel
dual batteries, dual alternator 440-amp, Uconnect 3, 5". No electrical modifications from factory.

On at least 10 occasions my batteries have been dead during first 14 months of ownership (purchased new Dec 2020). Seems very erratic, sometimes dying overnight, but almost always being dead if I have not driven the truck for 5+ days. Typically 100% discharged, such that there are zero interior lights, the key fob won't work, etc. I can successfully jump start (eventually) and the batteries then rapidly recharge with my dual alternators. A RAM dealer in Missoula said they had observed the issue with a Uconnect radio repeatedly attempting some update, but that often the flash for this radio required more than 12 hours!? .... I could not leave the vehicle for that long, so I later scheduled service in Colorado and left the vehicle for 4 days for evaluation and service. I was texted by the service advisor that indeed the radio was causing an intermittent phantom voltage draw (and causing the radio to irritatingly start-up at maximum volume, etc) but that a software update resolved the problem. (This contradicts the paperwork given to me that says they only observed 50-90 milliamp draw, and that I must keep the AUX switch shut off overnight regardless that nothing was plugged into it.) Unfortunately, my batteries were 100% dead after the truck was unused for five days after the service. The AUX switches were off as advised, and nothing plugged into the USB ports. Dual batteries should not 100% deplete in 5 days! The batteries reportedly test good (according to dealer), despite having been 100% discharged at least 6 or 7 times, and highly drained an additional 3 times. When the AUX switches are off (turning off the LED indicator lights), reportedly zero draw is observed on parasitic battery drain tests, perhaps supporting a hypothesis that it is a "computer-related" like UConnect trying to do an update at 3 am or something. But even this shouldn't pull enough amperage to kill dual batteries?

Of course, we have confirmed no interior lights left on. No glove box or underhood light in Tradesman. No added device like phone or GPS or camera. Battery cables seem tight; ground cables seem secure; no visually obvious frayed or damaged wiring based on a quick under-hood exam.

I have read from other RAM/Jeep/Dodge owners that they have had similar issues caused by the Uconnect radio, requiring a full replacement. Others have claimed that RAM got a batch of bad batteries. I have also read that discharging the auto batteries 100% flat at least 6 or 7 times will have done so much permanent damage to them that they will have permanently lost capacity. But dealer claims they are good.

I have been in contact with the service manager and he is willing to take the truck back in for further diagnostics. But I am >100 miles away, and the dealer won't provide an overnight loaner, and RAM has previously refused to pay the full cost of a rental car during previous warranty/recall service attempts. The service manager said he has never heard of a Uconnect radio causing an unusual parasitic draw, although his technician apparently documented it on my truck, based on the text messages I was sent. @RamCares was unable to help other than suggesting I take it to a dealer for evaluation.

I hate to have a brand new vehicle that is entirely untrustworthy. It seems to be a crap shoot as to whether the truck will start if I've left it parked overnight. Always starts perfectly with strong batteries if attempted within 12 hours. Sure, I can purchase a battery tender to solve my problems at home where I can plug it in overnight. But I'd like to be able to have a vehicle reliable enough to go on an overnight trip without being stranded.

Anyone out there been down this road that can offer some advice? Since it remains under warranty, I had hoped that RAM would solve it. However, I suppose I could start pulling fuses to disable the UConnect or something like that? Or I could purchase 2 new batteries out of pocket to see whether that helps. Dealer suggested I may want to pull the IOD fuse (ignition off draw) each time I park where it cannot be plugged into a battery tender. Or is there a more straightforward approach compared to trial and error, when error means being stranded somewhere? Is there an automated "battery isolator" approach that allows one of the dual batteries to be reserved just for starting the truck and prevent it from being drained?

Thanks for any input if you've experienced the problem, or have a suggestion for a battery isolator or other solution.

I know this post is a few weeks old. But replacing the batteries could be a good start.. if you have a bad cell or a bad battery it can kill both of them since they are parallel.. usually not 100% dead but still. There isn’t a battery that i know of that makes a full recovery from being 100% dead & its particularly worse for starting batteries.

Checking the amp draw and pulling fuses should give you a good idea on where the draw is coming from.. but I’d honestly start at the batteries themselves.. try disconnecting them overnight and see where your voltage is in the morning?

Process of elimination.. good luck

 

[mtwofeathers]

2020 Ram 3500 Tradesman, 6.7 HO diesel
dual batteries, dual alternator 440-amp, Uconnect 3, 5". No electrical modifications from factory.

On at least 10 occasions my batteries have been dead during first 14 months of ownership (purchased new Dec 2020). Seems very erratic, sometimes dying overnight, but almost always being dead if I have not driven the truck for 5+ days. Typically 100% discharged, such that there are zero interior lights, the key fob won't work, etc. I can successfully jump start (eventually) and the batteries then rapidly recharge with my dual alternators. A RAM dealer in Missoula said they had observed the issue with a Uconnect radio repeatedly attempting some update, but that often the flash for this radio required more than 12 hours!? .... I could not leave the vehicle for that long, so I later scheduled service in Colorado and left the vehicle for 4 days for evaluation and service. I was texted by the service advisor that indeed the radio was causing an intermittent phantom voltage draw (and causing the radio to irritatingly start-up at maximum volume, etc) but that a software update resolved the problem. (This contradicts the paperwork given to me that says they only observed 50-90 milliamp draw, and that I must keep the AUX switch shut off overnight regardless that nothing was plugged into it.) Unfortunately, my batteries were 100% dead after the truck was unused for five days after the service. The AUX switches were off as advised, and nothing plugged into the USB ports. Dual batteries should not 100% deplete in 5 days! The batteries reportedly test good (according to dealer), despite having been 100% discharged at least 6 or 7 times, and highly drained an additional 3 times. When the AUX switches are off (turning off the LED indicator lights), reportedly zero draw is observed on parasitic battery drain tests, perhaps supporting a hypothesis that it is a "computer-related" like UConnect trying to do an update at 3 am or something. But even this shouldn't pull enough amperage to kill dual batteries?

Of course, we have confirmed no interior lights left on. No glove box or underhood light in Tradesman. No added device like phone or GPS or camera. Battery cables seem tight; ground cables seem secure; no visually obvious frayed or damaged wiring based on a quick under-hood exam.

I have read from other RAM/Jeep/Dodge owners that they have had similar issues caused by the Uconnect radio, requiring a full replacement. Others have claimed that RAM got a batch of bad batteries. I have also read that discharging the auto batteries 100% flat at least 6 or 7 times will have done so much permanent damage to them that they will have permanently lost capacity. But dealer claims they are good.

I have been in contact with the service manager and he is willing to take the truck back in for further diagnostics. But I am >100 miles away, and the dealer won't provide an overnight loaner, and RAM has previously refused to pay the full cost of a rental car during previous warranty/recall service attempts. The service manager said he has never heard of a Uconnect radio causing an unusual parasitic draw, although his technician apparently documented it on my truck, based on the text messages I was sent. @RamCares was unable to help other than suggesting I take it to a dealer for evaluation.

I hate to have a brand new vehicle that is entirely untrustworthy. It seems to be a crap shoot as to whether the truck will start if I've left it parked overnight. Always starts perfectly with strong batteries if attempted within 12 hours. Sure, I can purchase a battery tender to solve my problems at home where I can plug it in overnight. But I'd like to be able to have a vehicle reliable enough to go on an overnight trip without being stranded.

Anyone out there been down this road that can offer some advice? Since it remains under warranty, I had hoped that RAM would solve it. However, I suppose I could start pulling fuses to disable the UConnect or something like that? Or I could purchase 2 new batteries out of pocket to see whether that helps. Dealer suggested I may want to pull the IOD fuse (ignition off draw) each time I park where it cannot be plugged into a battery tender. Or is there a more straightforward approach compared to trial and error, when error means being stranded somewhere? Is there an automated "battery isolator" approach that allows one of the dual batteries to be reserved just for starting the truck and prevent it from being drained?

Thanks for any input if you've experienced the problem, or have a suggestion for a battery isolator or other solution.

Well of course we have to address the dealer. Ever think that in today's world they ate not taught how to address draws that can take your batteries down? Today it's more like replace and hope for the best. Or denial because they really have no clue how to diagnose these issues. If you would like to know I can push a video at ya. But it will mean a more expensive electric meter than Harbor freight or one of the other box stores would carry. You'll need to be able to see miliamps and regular amps. Anything bigger than a 50 miliamp to me is a fail. And with a dodge one thing that fails most likely is a tipm. That's controlled by the computer. So if it comes down to the tipm you might even find a computer not shutting off a switch on the tipm board. Or a switch that has welded itself closed. Across the years tipms have gotten better. But not by much. That and things that run on power can be off a fuse inside. Or even the auto switch that leaves the power on for those minutes you first park and go into the house. Kinda nice if your home is not lighted up outside at night.
If you don't have a go to guy for things like this then do it yourself, not that hard just time consuming. And once you narrow it down. Tell the dealer what you found and how you found it so it can bypass him and go to corporate if he won't listen. There is no requirement for a guy at the front of the process having the knowledge to even take a tire off.

https://youtu.be/KF1gijj03_0

 

[schlite60]

I have a 2020 RAM 3500 CTD/HO single alt. After a year of ownership the batteries died. Took it into the dealer and they said that i had 2 Jeep batteries from a V-8 model. Dealer replaced both with the 94R (h7) batteries, cleared all of the codes. So far so good. Check your batteries and see if they are correct for the vehicle.

 

[PatriotMS]

I have a 2021 Ram 3500 MegaCab Limited... all the bells, whistles and even left the tablets plugged in.

My batteries died within 9 months. I am an Interstate Battery Dealer, so I upgraded with the AGM replacements and have not had any issues since... even after leaving it parked for a week.

 

[mcv1]

I owe the forum an update and solution. I finally found a RAM dealer who determined there was indeed a faulty battery. It required that I leave the truck for more than a week and pay for a rental vehicle during that time (no loaners available). After all of that, it was determined that one of the batteries was faulty. Stellantis reimbursed about half of my cost of the rental, but claim to have been maxed at $40/day. After replacing one of the two batteries, I have not had that problem recur. However, still if I haven't used the truck for a few days, the factory radio will start up at maximum volume and on some input setting that I have not recently used (like starting on AM radio at max volume) and it won't allow me to mute it until I get past the safety warnings. If I start the truck the same day, this never occurs. So I still suspect there is some weird draw by the satellite radio. But for now, I am no longer stranded in the mornings with the replacement of one of the batteries. FYI, given that I am 100+ miles from a RAM dealer, and that I had to pay for a rental car, it would have been much cheaper for me to replace them out of pocket than to try to get RAM to replace them under warranty.

 

[Daw14]

They should have replaced both of those batteries , the one they left will more than likely live a short life.

 

[tjfdesmo]

They should be replaced as a pair.

 

[06 Dodge]

I owe the forum an update and solution. I finally found a RAM dealer who determined there was indeed a faulty battery. It required that I leave the truck for more than a week and pay for a rental vehicle during that time (no loaners available). After all of that, it was determined that one of the batteries was faulty. Stellantis reimbursed about half of my cost of the rental, but claim to have been maxed at $40/day. After replacing one of the two batteries, I have not had that problem recur. However, still if I haven't used the truck for a few days, the factory radio will start up at maximum volume and on some input setting that I have not recently used (like starting on AM radio at max volume) and it won't allow me to mute it until I get past the safety warnings. If I start the truck the same day, this never occurs. So I still suspect there is some weird draw by the satellite radio. But for now, I am no longer stranded in the mornings with the replacement of one of the batteries. FYI, given that I am 100+ miles from a RAM dealer, and that I had to pay for a rental car, it would have been much cheaper for me to replace them out of pocket than to try to get RAM to replace them under warranty.

Don't understand why they did not load ***** them...

 

[SCUBAJAKE]

I just had a dual battery failure on my RAM 3500 Diesel. After it wouldn't start, I jumped it and took it my dealer. They found no parasitic draw but found both batteries with very low CCP and replaced both under warranty.

 

[JW2 Innovations]

Knock on wood no battery issues with my 2500 and batteries. Previous F250.....I went thru heck and back with battery issues. Parasitic draw as mentioned before is vital to do. And if none found, then alternator charging capability along with grounds being all there and working properly. Document what and how you check it as you go so if you have to start paying for labor they know what not to check again and can hopefully find it faster.

How To Perform a Parasitic Draw Test - EricTheCarGuy

http://www.ericthecarguy.com/This video has been a long timing coming and is one of the most requested things I get is about batteries going dead overnight s...

youtu.be