Alternator or battery or ?

[thebull55]

I have a 2018 Tradesman with the 3.6L. 2 nights ago when I was leaving for work, I put the key in and everything turned on per normal. But when I tried to start I just got click and nothing. All lights and such stayed on. I ended up getting the charging block out and it started right up.

The next morning, it was sluggish but started.

Now tonight it reluctantly started but I noticed that the headlights (led) were kind of flickering. As I drove down the road, I looked at the volt gauge on the dash and it was flipping from 13-15 consistently. Lights continued to flicker.

Does this sound like the battery or the alternator? I work over night so I plan on getting the battery checked in the morning.

Any guidance would be greatly appreciated.

 

[mikeru]

Could be either. Any auto parts store can test both without the need to remove them from the truck.

 

[thebull55]

Thanks Mike. That is my plan. I am just trying to wrap my head around it so I have a basic clue.

 

[SitKneelBend]

Thanks Mike. That is my plan. I am just trying to wrap my head around it so I have a basic clue.

Every time I've encountered this on these trucks it has been the battery. I don't know if I've ever come across someone where the issue was the alternator.

 

[thebull55]

That is definitely my hope. It isn’t the newest battery. Getting it tested this am. Thanks.

 

[thebull55]

I guess that was easier that I remember. Advance Auto hooked it up and the battery was showing 10v. After it was started, it showed 0 cca and was dead enough that he couldn’t do the alternator test. So battery it is, for now.

Sorry, I probably should have waited to test it before I posted. Thank you for the input though. Much appreciated.

 

[mikeru]

Every time I've encountered this on these trucks it has been the battery. I don't know if I've ever come across someone where the issue was the alternator.

I was going on my experience with past vehicles I've owned for the last 40 years since I've never had an issue like this on a Ram truck. Although I was also leaning towards the battery being the issue based on the seemingly high number of OEM battery problems I've seen posts about compared to alternator problems. It's always good to test the system though. Have you seen this type of issue a lot on these trucks?

 

[SitKneelBend]

I was going on my experience with past vehicles I've owned for the last 40 years since I've never had an issue like this on a Ram truck. Although I was also leaning towards the battery being the issue based on the seemingly high number of OEM battery problems I've seen posts about compared to alternator problems. It's always good to test the system though. Have you seen this type of issue a lot on these trucks?

Yep, and I've seen it on mine several times as the battery is going out or I accidentally forced it out of service early. With all of the computer modules onboard, many of the functions are actually controlled by "target voltages" and if they are off it can cause some interesting/unexpected results.

 

[RamDiver]

Yep, and I've seen it on mine several times as the battery is going out or I accidentally forced it out of service early. With all of the computer modules onboard, many of the functions are actually controlled by "target voltages" and if they are off it can cause some interesting/unexpected results.

It would appear that voltage regulation is a foreign concept in Ram trucks.
Or the minimum operating voltage for successful regulation is often considerably more than 12 VDC.

The battery on my truck is coming up to the end of its life and hovering around 12 or 12.1 VDC. Strangely, there are no comm errors or DTCs of any sort.

.

 

[inuyasha-rules]

My guess is the battery. These trucks cycle the alternator off at low rpms to save fuel if the voltage is high enough. If the battery has low capacity it will go high, turn off, drop quickly, turn on and keep cycling.

 

[CanuckRam1313]

It would appear that voltage regulation is a foreign concept in Ram trucks.
Or the minimum operating voltage for successful regulation is often considerably more than 12 VDC.

The battery on my truck is coming up to the end of its life and hovering around 12 or 12.1 VDC. Strangely, there are no comm errors or DTCs of any sort.

.

 

[RamDiver]

My guess is the battery. These trucks cycle the alternator off at low rpms to save fuel if the voltage is high enough. If the battery has low capacity it will go high, turn off, drop quickly, turn on and keep cycling.

I don't think there was ever a doubt, but I'm glad to hear you have decided on a position.

You may want to read post #6.

I've heard discussion of this alternator shutdown but have yet to locate any supporting evidence.

Do you have any technical documentation to support this concept?

.

 

[inuyasha-rules]

Do you have any technical documentation to support this concept?

No technical documentation, but at idle with a high electrical load, I can watch my voltage fluctuate up and down, and hear the alternator cycle on and off. It bounces between 12.5 and 13.5 in a rhythmic pattern, and doesn't do it while driving. I've seen other posts about it and the general consensus is it sqeeks out an extra 0.5mpg for cafe standards.

 

[crash68]

I can watch my voltage fluctuate up and down, and hear the alternator cycle on and off. It bounces between 12.5 and 13.5 in a rhythmic pattern

I doubt your hearing the alternator cycle on/off, it doesn't cycle like an AC compressor which I'm guessing is what your hearing cycle.
To control how an alternator charges the battery, the voltage applied to the rotor is raised or lowered via PWM to control the output voltage/current.

 

[RamDiver]

No technical documentation, but at idle with a high electrical load, I can watch my voltage fluctuate up and down, and hear the alternator cycle on and off. It bounces between 12.5 and 13.5 in a rhythmic pattern, and doesn't do it while driving. I've seen other posts about it and the general consensus is it sqeeks out an extra 0.5mpg for cafe standards.

What you're describing sounds more like a questionable voltage regulator or some other irregularity.

I've never seen this happen on my Warlock, but I don't spend too much time in the truck while idling.

One of the benefits of country living is that there aren't many traffic jams.

I would suspect that if it were designed to cycle on/off by use of the PCM, we would see this more often with light loads, when a fully charged battery alone is sufficient to power the load.

I don't think anyone can hear electrons in a conductor or any solid-state device switching. I'm not sure what you're hearing.

I've heard discussions on this topic, but until I see technical documentation to support the concept, it's just another rumour to me.

.

 

[inuyasha-rules]

I don't think anyone can hear electrons in a conductor or any solid-state device switching. I'm not sure what you're hearing.

It's a high pitched whine type noise, similar to old crt TVs, and you can also hear the engine take up a bit of load. I've noticed it in almost every other ram 1500 I've been in as well.

 

[rwahrer]

I have a 2018 Tradesman with the 3.6L. 2 nights ago when I was leaving for work, I put the key in and everything turned on per normal. But when I tried to start I just got click and nothing. All lights and such stayed on. I ended up getting the charging block out and it started right up.

The next morning, it was sluggish but started.

Now tonight it reluctantly started but I noticed that the headlights (led) were kind of flickering. As I drove down the road, I looked at the volt gauge on the dash and it was flipping from 13-15 consistently. Lights continued to flicker.

Does this sound like the battery or the alternator? I work over night so I plan on getting the battery checked in the morning.

Any guidance would be greatly appreciated.

Check the running voltage at the batter, you should have close to 14 volts if its less its the alternator,

 

[thebull55]

Check the running voltage at the batter, you should have close to 14 volts if its less its the alternator,

It was showing about 10 volts and 0 cca. Replacing battery Wednesday.

Thanks.

 

[turkeybird56]

It was showing about 10 volts and 0 cca. Replacing battery Wednesday.

Thanks.

Doorstop there.

 

[3CUMMINS]

I have a 2019 3500 4WD HO diesel.
Last June, the console screen was changed due to delamination.
And then, the fun started.
My son had the truck from May/June until it was put away for the winter. We have used a Battery Minder 128 every winter since I bought the truck new and never had a problem.
He had said that he had to plug in the Battery Minder because the batteries were low and slow to roll the truck over.
This is in September. I live in southern Ontario and it does not get "that" cold. He used the battery minder until the truck was put away.
We wrote the need to use the minder this early off as they were the original, marginal ones that came with the truck
so we could stave off installing new ones over the course of the winter.
After every hibernation, I get the oil changed. I made the appointment and told them previously of the console screen turning off and on while I was driving. It is about 25 miles to the dealer and it shut off and turned back on 3 times on the way there and 5 times home.
I arranged to take the truck back and let the "tech" who switched the screen see if there was anything that he could find about the restarting and told them that the batteries were new and were not holding a charge either. He refreshed the console two or three times. He said nothing seemed wrong He didn't drive it and it didn't restart while he was working on it, so the answer was no, and a $189 bill. He also said that it was because we had put the battery minder on backwards, the cables.
The console worked until about a mile down the road and restarted with another 5 before I got home.
I called them and let them know that it was just as bad and explained that the battery minder not only had a light that showed if the minder was not hooked up correctly a red light lit up.
The kicker is that the cables only attach to the battery one way. There a two different ends on the cables and unless you are a proponent of square pegs in round holes, I could hook it up correctly blindfolded.
My husband took out the meter and checked the fuses and the alternator. Alternator was fine and there were the fuses showed no leaking.
My son reminded me about having to use the battery minder when this problem arose.
I have to contact them to look at the problem again but would seem that it all started with the console screen and its installation.
Has anyone else had this kind of issue? Was the problem fixed and what was the actual cause.
Thanks.