2021 1500 Battery dead out of nowhere.

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Tuke

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I have a 2021 1500 and I went to go to work the other day and it was dead and my check engine light was on. I had driven it thr previous day without issue.

I jumped it as I had to get to work and watched my battery display. The voltage rose as I drove to 13.6. When I went to leave for home the following morning, it was dead again. After I jumped it to get home, I checked the resting voltage and it was giving me 12.4 volts.

I purchased a new battery and installed it this morning, but while driving it and watching my battery display, I noticed my volts were all over the place. Anywhere from 13.9 to 12.6.

I would hope that the alternator isn't bad after barely 3 years, but does anyone have any insight to what may be going on?

Thanks in advance!
 

LouM

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Good luck with your battery change. Your already ahead of mine. When my failed it set several DTC's and my pickup wouldn't shift out of first gear or engage 4wd or the diff lock. I had a check engine light and a tractioncontrol/stability control light on. It took a code reader and a reset to clear mine up. My voltage had been running around the 13.6 volts whenever I had looked at it, after the battery change it went to 14.1 for a day and now is back to 13.6 to 13.8 volts.
 
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Tuke

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Well, I just drove to a Sr appointment and it started when I came out and my check engine light is now off.
I wouldn't think a resting voltage of 12.4 would be enough to cause this but I'm in no way, shape, or form a mechanic.

I'll probably stop at Auto Zone and have them test the alternator and scan it for any codes so hopefully all is well.
 

rzr6-4

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Well, I just drove to a Sr appointment and it started when I came out and my check engine light is now off.
I wouldn't think a resting voltage of 12.4 would be enough to cause this but I'm in no way, shape, or form a mechanic.

I'll probably stop at Auto Zone and have them test the alternator and scan it for any codes so hopefully all is well.

I would lean towards alternator, but if the test comes back saying its still good then you're back to troubleshooting.

I would disconnect the battery and use an ammeter to bridge from the battery terminal to the cable to see if you are having parasitic drain with everything off. A few mA is fine, but if you have a double digit number then something is draining your battery while sitting.
 
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Tuke

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I would lean towards alternator, but if the test comes back saying its still good then you're back to troubleshooting.

I would disconnect the battery and use an ammeter to bridge from the battery terminal to the cable to see if you are having parasitic drain with everything off. A few mA is fine, but if you have a double digit number then something is draining your battery while sitting.
Thanks, It started fine just a while ago and the check engine light is off now so I'm hoping that is a good sign. I'm still gonna get it checked to be safe so we shall see.

It was just really weird. I never had a slow start or anything. I even left my dome light on once all night and it fired right up. I do have a dash cam that stays on all the time but it has never caused an issue previously so who knows.

The more advanced our vehicles get, the mores stuff to malfunction, and I'm quite certain that with the exception ofcreplacing the battery and changing the oil, there isn't much else I am qualified to do aa far as maintenance and repairs on this thing!!

Thanks for the advice!
 

Tulecreeper

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Thanks, It started fine just a while ago and the check engine light is off now so I'm hoping that is a good sign. I'm still gonna get it checked to be safe so we shall see.

It was just really weird. I never had a slow start or anything. I even left my dome light on once all night and it fired right up. I do have a dash cam that stays on all the time but it has never caused an issue previously so who knows.

The more advanced our vehicles get, the mores stuff to malfunction, and I'm quite certain that with the exception ofcreplacing the battery and changing the oil, there isn't much else I am qualified to do aa far as maintenance and repairs on this thing!!

Thanks for the advice!
I used'ta could, back when there was enough room under the hood I could sit in the engine bay and work on it in the shade. :driver:
 

RamDiver

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Thanks, It started fine just a while ago and the check engine light is off now so I'm hoping that is a good sign. I'm still gonna get it checked to be safe so we shall see.

It was just really weird. I never had a slow start or anything. I even left my dome light on once all night and it fired right up. I do have a dash cam that stays on all the time but it has never caused an issue previously so who knows.

The more advanced our vehicles get, the mores stuff to malfunction, and I'm quite certain that with the exception ofcreplacing the battery and changing the oil, there isn't much else I am qualified to do aa far as maintenance and repairs on this thing!!

Thanks for the advice!

While you're at AutoZone having the alternator tested, have the battery load tested as well.
Yours wouldn't be the first defective new battery.

Also, being in a hot climate like Texas, 3 years is the average life expectancy for an automotive battery. As the battery ages, and starts to become marginal, the additional load of the dash cam may have pushed it over the edge.

AFAIK, my '21 Warlock has the brains to disable any interior lighting that I might forget turned on, so, forgetting the dome light on shouldn't matter.

.
 
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dsherman26

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Good luck having your "alternator" tested, since the 48 volt motor generator and the DC to DC converter behind the back seat are what charge the 12 volt battery. It's normal for the 12 volt battery voltage to vary considerably on modern vehicles to better manage the state of charge of the battery. My old Traverse could vary between 12.3 and 14.6 with the engine running and that was normal. Sounds like you just have a faulty battery, and the check engine light was probably for low battery voltage until it got recharged. I don't trust Autozone's battery box when it reported the alternator in my Honda faulty, even though it was working perfectly according to Honda's testing procedure.
 

RamDiver

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Good luck having your "alternator" tested, since the 48 volt motor generator and the DC to DC converter behind the back seat are what charge the 12 volt battery. It's normal for the 12 volt battery voltage to vary considerably on modern vehicles to better manage the state of charge of the battery. My old Traverse could vary between 12.3 and 14.6 with the engine running and that was normal. Sounds like you just have a faulty battery, and the check engine light was probably for low battery voltage until it got recharged. I don't trust Autozone's battery box when it reported the alternator in my Honda faulty, even though it was working perfectly according to Honda's testing procedure.

A good catch, I missed the E-Torque feature in the signature line.

That does create more complications. :cool:

.
 
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