2017 RAM Cummins Low Voltage Fault Diagnose and Repair

[@weberlnk]

Found the exact same thing recently on my '19 Power Wagon. Positive terminal on the alternator was not even finger tight. Thanks for the video -- saved me a trip to the dealership.

[@angeloiezzi7054]

So, I JUST left the dealership (for the 3rd time) only this time the light was still on. The service manager spent 30 minutes on the truck (told them the light will be going out soon so please run diagnostics ) After 30 minutes he explained he is pretty sure my Alternator is bad. Well the Ecodiesel alt is 1200 just for the part. As it stands I was supposed to drop it off this morning but I did not. I just watched your video and will be heading STRAIGHT to the bolts as soon as I get home !!!!! OMG I hope that is it. Thank you in advance.

[@smartmotives]

Was it it!? Got the same issue I am diagnosing.

[@angeloiezzi7054]

@@smartmotives I still don't know. It stopped for the past month. So I'm lost

[@paulwarren1586]

After having my 2012 RAM 2500 CTD for almost 7 years now, the check engine light came on for the first time, I got the P0562 code which of course narrows it down to either the batteries or alternator, after watching this video I hooked my volt meter to each battery and when I started it the voltage went down to about 8 volts before the engine fired up, the good thing is that the voltage went back up to 14.33 volts when the truck is running so yeah I need new batteries, I replaced the batteries in 2015 with interstate batteries so at least I got 5 years out of them with really no issues.

[@DownsizingMakesCents]

Thanks for posting this, i have the same problem, it gives the low voltage warning when i hit bumps, so i think it must be a loose connection between the batteries and the alternator. Larry

[@roadservice6365]

Also if this didn’t help check your 250A fuse on the positive battery ( passenger side)

[@jasonviers2586]

Having very similar issues with my Dodge. Did you ever find the true cause of the low voltage?

[@donearl6675]

i have a 2019 ram.i had my did the same today.checked the battery and alt. with a volt meter.all the reading are good.but i had my doors open and turn on the acc quite a bit.was putting in some additional lights.i think doing all that may have cause the trouble..maybe. went back out and restarted my truck 2times.fired over and the volt meter still says 14 blah blah volts.plan to put it on a charger anyway tomorrow.

[@Vorticosejeffy7]

Add a big three upgrade I went with 0 gauge and it solved my issue

[@mavrick0pm]

Had the exact same issue with my 17 3500. Only difference was when it was built the rubber boot had been squeezed between the nut and stud on the secondary alternator. Due to this the cable and stud had been arcing to the point that when I figured out the issue I couldn't tighten the nut down with the amount of damage on the threads. So that simple little mistake at the factory cost RAM a brand new alternator.

[@andrewdrey8431]

Thanks for helpful information!!

[@oblivion85]

Have a 2015 1500 hemi. The low voltage/battery save mode lights came, took it to have it read at autozone they said that the battery was fine and that it was the alternator, so I took out the alternator and had it tested at the same autozone and it passed. Also the power steering became real stiff where I have to use all my strength to turn. Any thoughts?

[@aaronsrose]

The power steering failing could be it. I believe the hemi trucks use electric power steering so if that motor supported out it could cause a serious drain on the charging system until it burned through. That might cause your symptoms.

[@Hostility1812]

Power steering fuse is on the battery terminal

[@pythonprofreak7522]

I have the same problem on my 2017 RAM 3500 Laramie Longhorn Cummins. This is the third time it happened. "Battery Low Voltage". On the cummings forum they are saying the same thing. It seems like this is a common problem now but Chrysler hasn't categorized this as part of the recall (or simply ignoring it).

[@charlescase1204]

I am having the same problem put in new alternator and batteries made sure all connections are tight and still has problem. Dealer ship said i needed new computer for 4000.00 they said the regulator for the alternator was in the computer and had gone bad. Does this sound right to you guys?

[@Breakoutapparel]

I chased this problem for a long time it's the little black and silver squares on top of. the positive terminals that's the culprit.

[@ranch5223]

How did you come to this conclusion and what was the fix or alternative....I have same problem

[@curtsmith7596]

And what is the part called, I've replaced batteries, alternator, battery temp sensor, its driving me crazy

[@nathanielwilson3174]

not always. i replaced my fuses as well. didnt fix it.

[@06waterboy]

@@nathanielwilson3174what fixed yours. I’ve been having same problem

[@golffoxtrotyankeehooligan222]

I have the 18 6.7L and I keep getting the message envelope my truck has power save mode that continues to display but Dodge claims nothing is wrong. I'm considering buying and upgrade alternator. Look and see if you can shut off your engine power to zero seconds after you turn off your truck, my option is in the radio to do that

[@aaronsrose]

I haven't set the power-off to immediate, but it does kill it when I open the door, so that's usually pretty quick. If you are getting the Low Voltage warning, I'd definitely confirm all the wiring connections and if they are good, I'd try to run a good voltmeter to see exactly what the truck is doing when it throws the fault. If the charging voltage drops below 13.0, it will throw the code even though that may be good enough to keep everything charged up. Since tightening the loose connection on mine, it's been fine for 20k miles. You might also be able to monitor the voltage with an OBD2 scanner. That might be easier than a volt meter if you have one available. Good luck!

[@manuelgonzalez1652]

Did you figure out what was going on?

[@JCCARLITOS23]

Thanks 😊

[@eh235]

11v at start up is common then it jumps to 13v to 14v is how both my Ram trucks (2014 &2018) voltage runs

[@djsly0801]

Hopefully someone responds but I’ve been having a problem with my 2014 ram 2500 I have the single alternator setup I went to Missouri for 2 weeks and the batteries completely died I jumped the truck, the truck ran fine but after a 4 days battery light came on and alternator stopped charging the batteries got a new alternator and the alternator started smoking and burned out the alternator fuse was it just a bad alternator? Or something else is going on

[@aaronsrose]

Howdy! Have you changed the batteries recently? If you have the OEM batteries still in the truck I would expect they are junk. The alternator failure is odd, but until you confirm that both batteries are good, excessively low battery voltage can increase the amp draw and cause odd malfunctions.

[@djsly0801]

Aaron Rose I got the duralast platinums but I bought a new alternator and installed it with the original batteries and the batteries were reading 11ish volts and the truck started and that’s when the alternator started smoking so now I got a new one tested it and it passed, now I’m just waiting for a day off to install it I’m charging the batteries the day before so they’re at full power

[@aaronsrose]

Yowza. Definitely charge those batteries. Anything below 12.2V is very weak. Running them down into the 11's can damage them pretty quickly. A battery at 100% should read in the 12.8v range when tested with no load. If the batteries don't come back, I've had very good luck with the AutoZone warranties over the years. Good luck.

[@djsly0801]

Aaron Rose it was the battery’s I’m an idiot I should’ve known better im at 14 volts

[@golffoxtrotyankeehooligan222]

I have 2018 Ram 2500 6.7L it's about 12° outside and my garage heater isn't working so its about the same in my garage. Its started and ran daily I only have 8,800 miles I'm in battery saver mode and the dealership claims its normal "bullshit". Just fyi press your cruise control button then set button while parked it will idle the truck to 1k if you press the resume up it will rev up 100 rpm up to 1,400 rpm

[@CSXtrackworker]

Battery saver mode is normal when the air temp drops below freezing. When you do a cold start on your truck the grid heater continues to cycle on and off to try to keep the air warm for up to a minute that is going into your cylinder heads. It is trying to protect the batteries. Once battery saver mode turns on it will stay on your message board until you turn the truck off. It resets it. It doesn't mean it is in continual mode. It's just a cold start thing. Once the air temp is warmer than freezing point it does not turn on. Mine is a 2018 Ram 3500.

[@ranch5223]

@@CSXtrackworker I have a 2018 ram 2500 It is Winter not freezing but cold my low voltage like came on can you elaborate on what you are talking about

[@CSXtrackworker]

@@ranch5223 if you have a low voltage light message on instead of a battery saver message then you need to check to see if the connections on your battery terminals and alternator are tight. If they are tight then you may have a battery with low voltage.

[@codylyons7102]

On the 2018 eco boost i noticed i will have low voltage it drops to 10-11 volts and immediately goes too 13 volts consistent and the message for low voltage goes away at full operating temp? Anyone know why?

[@aaronsrose]

That is pretty odd. I wonder if the alternator is wonky when cold. I'd clean the connections and possibly have the nater tested to see if it acts up on its own before replacing it.

[@josepaiz2468]

did the battery light went off? I'm having same problem with my 2015 ram , but my case I just put two brand new batteries and it shows low voltage and can't figure it oyt

[@aaronsrose]

Howdy! Yes it's been perfect for the last 4000 miles. Check your alternator output voltage and if it's 13.8 V or so, confirm all the connections on all the wires are good and tight. Good luck!

[@pythonprofreak7522]

Two months after the purchased this messaged popped up. I thought it was new so I was simply ignoring it . So it happened again on Nov 17 and today. All the cables are tight. I will try to send it to the dealer to be checked.

[@alanjohnson2347]

so what happend at dealer? did they fix it? what did it take to fix it?????

[@lucasfallert4031]

I am also curious if you figured anything out.

[@patrickoconnor1219]

I have a 2018 2500 Mega Cummins with 12K miles - "battery saver mode" keeps coming up - I read on some forum (which I need to find again) that it can be the intake manifold preheater. Anyone know more info on this?

[@JAS-zb7hk]

I have a 2017 ram 1500 6 cyl I had my battery light on I got a new battery and still the battery is on Any ideas of what to check next? Thanks

[@aaronsrose]

First things are clean connections to the battery terminals. Then make sure the alternator is putting out 14 volts. Finally check all the connections to the alternator.

[@Jason-hc7nq]

Hey I have a dodge ram 1500 2017 3.6 and I change Alt battery and low voltage still showing plz help I'm 2000 in

[@thormx47]

This keeps popping up on my 2018 ram 2500. I drove 20 min yesterday and the light kept coming on then off. Dash reads 13v all the time

[@aaronsrose]

Being pretty new, I'd definitely check all the battery and alternator connections, if they're tight it could be the batteries or the alternator itself. In that case, hopefully warranty will take care of it. Good luck!

[@thormx47]

I just went through and checked all the battery connections & the alternator. Everything was tight except I got a few turns out of the pos and neg on the drivers side. Now the light is on right away and it’s reading 12v. I’m going to check the batteries tomorrow and the alternator. Thanks for the video!

[@ranch5223]

@@thormx47 what was the outcome my 2018 Ram2500 started the dam low voltage light shit too

[@thormx47]

Dealer fixed it under warranty. Passenger side battery was bad and there was a short at the generator

[@eddypetra5660]

I have the same thing with my 2017 3500 right now. Just put in 2 new batteries and 2 different alternators. Truck has 110k miles. Started 3k miles ago. Went down to 8 volts the other day. Put a new alternator jumped it drove fine for next 400 miles till I made it home and the entire time the battery light came on and of. Voltage went from 12-13. Anyone know what’s going on? Thanks

[@aaronsrose]

Hmmmm. That's odd it still does it after replacing about everything in your truck. If it's flipping around 12-13v it's still charging as you saw in the video. Just not as much as it should. Any aftermarket stuff like a stereo amp or big lights? If so I'd disconnect them short term to rule them out. Then I'd triple check all the connections and maybe even try to see if there is a broken grounds strap somewhere. Good luck!

[@frye1corvette678]

Pcm update us available

[@nathanielwilson3174]

im on my 3rd altenator and batteries. I keep throwing the same light. checked all connections and i have a single altenator on my 2017 2500. I even changes the fuses on the terminal lines of the battery. no luck so far.

[@michoacan91davi]

So your saying the fix was a loose nut that needed to be tightened on the secondary alternator?

[@aaronsrose]

Yup. That one loose connection was the problem. Almost 14k on it now and never happened since tightening that terminal. Thanks!

[@michoacan91davi]

@@aaronsrose nice thanks for the info

[@mujeebrahmanparuvingal4513]

Check engine light