Battery problems after relay safety recall repair

[Lady_Violet_XXI]

Saga of the dead battery. Plot twist.

2021 2500 Big Horn
Push-button start. No remote start.

Bought used from dealer 2/23. 67k miles. Towed rv trailer with zero problems until 10/23.
> 9/28 - 2 safety recall repairs - IAGH relay replaced, tailgate striker inspected. Also had front end alignment and requested maintenance inspection (I suspect this last wasn't really done).
No immediate problems other than questionable alignment job.

> 3 weeks later. Rented a small uhaul trailer (5-pin plug). Stayed hitched overnight. Next morning won't start. Says wait for preheat. Flashed fuel filter message (odd because it had 40% life left).
Towed back to dealer. All they did was put on battery charger for several hours and started. Asked me if it was hooked up to anything (like a trailer). Yes. Was advised a short in the trailer electric probably drained battery. Also, primary battery would only charge to 80%, suggested I replace soon. Quoted $600, I decided to get the battery elsewhere. Drove it home.
> 2 days later, battery dead.
Called AAA to replace battery. Rookie hooked up packs to both batteries, no start. Says it's not batteries and leaves.
> I research. Find out you can't jump a diesel like that.
> 2nd call to AAA for battery. This guy does an actual test, charge etc. Primary battery tests bad, replaced. Starts fine.
> Zero problems for 2 months, even pulling rv, sitting several days etc.

>Wednesday (3 days ago) dead battery. I hook up to jump vehicle, charge about 30 minutes, it starts. Plan to take it in until I see that dome light stays on, even after I'm driving. Suspect that drained battery while it sat 3 nights. Tech agrees. I plan to bring it in after holiday weekend. Make sure all lights go off after I lock it.
> Thursday, starts fine.
> Friday - Not as "dead" as before, but won't start. Diesel preheat cycling, "replace fuel filter" message then engine light. Just like first time. Alternator says 11v, but I don't know if that's an accurate read.

I've seen threads about trucks having parasitic draw, but this is bizzare. Dealer who performed recall says it can't be the new relay because it was fine for 3 weeks, so it must have been the rented trailer. I have no way to verify if they found a problem with that trailer after I returned it.
Everything seemed fine after the new battery. Now this.
Has anyone had problems following the relay recall fix? IF the rental trailer harmed the battery, that battery was replaced.
I'm taking it in to a place recommended by someone I trust. Now has 72k miles.

If you made it to the end, thanks.

 

[AH64ID]

Sounds like you only replaced one battery, so that’s likely your issue. The old battery is draining and damaging the new battery.

Always replace batteries on these rigs in pairs.

There is no “primary” battery, they work together as one larger battery.

The dome light will turn off after a while to keep from draining the batteries, that likely isn’t your issue… just crappy batteries these days.

Voltage on the dash is accurate. 11V is low, unless the grid heater was doing a post-heat cycle.

Getting the grid heater recall done is likely just a coincidence.

Go get another new battery and hope that the first new battery wasn’t killed by the old battery.

 

[Lady_Violet_XXI]

Sounds like you only replaced one battery, so that’s likely your issue. The old battery is draining and damaging the new battery.

Always replace batteries on these rigs in pairs.

There is no “primary” battery, they work together as one larger battery.

The dome light will turn off after a while to keep from draining the batteries, that likely isn’t your issue… just crappy batteries these days.

Voltage on the dash is accurate. 11V is low, unless the grid heater was doing a post-heat cycle.

Getting the grid heater recall done is likely just a coincidence.

Go get another new battery and hope that the first new battery wasn’t killed by the old battery.

Yes, I know they're parallel batteries, I just used the word "primary" to be clear about which one tested bad. The second battery tested fine. I pushed the tech about what you just said (always replace both). He said it would be a waste of money, especially since it wasn't old. He could have sold me a second battery and taken my money. I'm going to ask the new place about it. And see if the new battery (under warranty) is defective.

But it's strange. All good for 2 months. It often sat for days at a time. I've kept my eye on the alternator gauge.
Suddenly, drained completely in 3 nights. Charged 30 minutes, starts.
Next day, starts fine. 14v.
Then drained again overnight.

The dome light did not turn off like it was supposed to. I was a few miles down the road and one was still on - the other off. A friend with a RAM 2018 said if he has the interior dimmer turned ask the way up, the lights don't time out. But no idea if that's true for my year/model. Have you ever heard of that setting?

 

[AH64ID]

Yes, I know they're parallel batteries, I just used the word "primary" to be clear about which one tested bad. The second battery tested fine. I pushed the tech about what you just said (always replace both). He said it would be a waste of money, especially since it wasn't old. He could have sold me a second battery and taken my money. I'm going to ask the new place about it. And see if the new battery (under warranty) is defective.

It’s not clear which battery you are talking about, since they’re isn’t a primary and secondary battery. There could be reasons to call either on primary if one were so inclined.

When talking about the batteries label them as drivers side and passenger side.

But it's strange. All good for 2 months. It often sat for days at a time. I've kept my eye on the alternator gauge.
Suddenly, drained completely in 3 nights. Charged 30 minutes, starts.
Next day, starts fine. 14v.
Then drained again overnight.

Sounds like a failing battery, and these modern trucks are very sensitive to battery state of charge.

The dome light did not turn off like it was supposed to. I was a few miles down the road and one was still on - the other off. A friend with a RAM 2018 said if he has the interior dimmer turned ask the way up, the lights don't time out. But no idea if that's true for my year/model. Have you ever heard of that setting?

There is a switch to turn the dome light on which will keep it on going down the road and after the truck has been shut off (for a time, but not overnight) Has that been pressed?

Even if you manually turn them on they will eventually time out on your 21, and his 18 too.

 

[H3LZSN1P3R]

This has nothing to do with the recall thats just silly trying to play that as a cause. Your batteries should have both been replaced the donkey at AAA should know better than just replacing 1. If your voltage gauge says 11 volts then thats what it is you likely have a bad battery again.

 

[areuriding]

Yes, I know they're parallel batteries, I just used the word "primary" to be clear about which one tested bad. The second battery tested fine. I pushed the tech about what you just said (always replace both). He said it would be a waste of money, especially since it wasn't old. He could have sold me a second battery and taken my money. I'm going to ask the new place about it. And see if the new battery (under warranty) is defective.

But it's strange. All good for 2 months. It often sat for days at a time. I've kept my eye on the alternator gauge.
Suddenly, drained completely in 3 nights. Charged 30 minutes, starts.
Next day, starts fine. 14v.
Then drained again overnight.

The dome light did not turn off like it was supposed to. I was a few miles down the road and one was still on - the other off. A friend with a RAM 2018 said if he has the interior dimmer turned ask the way up, the lights don't time out. But no idea if that's true for my year/model. Have you ever heard of that setting?

If interior dimmer is up all the way the light stays on.

 

[H3LZSN1P3R]

Besides these batteries are so simple to change why pay someone to do such a mundane task

 

[Lady_Violet_XXI]

Besides these batteries are so simple to change why pay someone to do such a mundane task

When you're disabled and have no help, you pay. Why are you being so nasty? If you can't be helpful, why comment at all?

 

[Lady_Violet_XXI]

New "symptom." Whether or not the relay is affecting the battery, it's not working correctly. Press start, it's supposed go through the preheat and then automatically start. Instead, it goes back to "Press Start." After I press start again, it either starts or does preheat a second time, then starts. It didn't used to need a second push. And I noticed that even when the power/volts are fine. I live in Tampa, FL. It can get chilly enough to need preheat (especially at night) but the engine isn't in freezing conditions.

 

[AH64ID]

New "symptom." Whether or not the relay is affecting the battery, it's not working correctly. Press start, it's supposed go through the preheat and then automatically start. Instead, it goes back to "Press Start." After I press start again, it either starts or does preheat a second time, then starts. It didn't used to need a second push. And I noticed that even when the power/volts are fine. I live in Tampa, FL. It can get chilly enough to need preheat (especially at night) but the engine isn't in freezing conditions.

Replace the other battery and give them both a good charge.

Your symptoms are all from low voltage.

If you have issue with 2 new fully charged batteries then you can start looking for abnormal draws.

So far nothing you have described is abnormal for weak batteries.

 

[H3LZSN1P3R]

When you're disabled and have no help, you pay. Why are you being so nasty? If you can't be helpful, why comment at all?

Not being nasty just asking its so easy to change the batteries why not do it yourself, if you are disabled thats a perfectly good explanation on why you paid for the service. It is not to be rude it was more about saving you money.

 

[H3LZSN1P3R]

New "symptom." Whether or not the relay is affecting the battery, it's not working correctly. Press start, it's supposed go through the preheat and then automatically start. Instead, it goes back to "Press Start." After I press start again, it either starts or does preheat a second time, then starts. It didn't used to need a second push. And I noticed that even when the power/volts are fine. I live in Tampa, FL. It can get chilly enough to need preheat (especially at night) but the engine isn't in freezing conditions.

Are you keeping your foot on the brake through the preheat cycle?

All new vehicles are very funky with low voltage issues when the batteries get weak they cause all kinds of odd issues. I have been pretty lucky my 19 is still with the original batteries as most have had to change them out within a couple of years.

 

[jebruns]

But it's strange. All good for 2 months. It often sat for days at a time. I've kept my eye on the alternator gauge.
Suddenly, drained completely in 3 nights.

I have a lot of batteries around in vehicles, motorcycles, boats, RV's, generators, etc. And have dealt with them all for a lot of years. Non-deep cycle batteries that have been in use for a while can be ruined quickly with one "deep cycle" draining. They are not made to handle that kind of use well. So IMO, the trailer starting all of this by draining your battery makes sense.

 

[Nick]

Buy a battery tester on line . Not expensive and very easy to use . you can run battery life , volts ,cold cranking amps etc . Saves you much time money and frustration when trying to figure out if they are good or bad .

 

[Blythkd1]

Lots of good feedback here that is dead on. But if you're still wishing to rule out the grid heater relay, it's pretty easy. Just unhook it. It's a nut that takes a 10mm wrench on top of the passenger side battery on my '22. Bet it's the same on the '21. That would give you some peace of mind on the relay issue but I agree with all the other comments, probably a simple voltage issue.

 

[AH64ID]

New "symptom." Whether or not the relay is affecting the battery, it's not working correctly. Press start, it's supposed go through the preheat and then automatically start. Instead, it goes back to "Press Start." After I press start again, it either starts or does preheat a second time, then starts. It didn't used to need a second push. And I noticed that even when the power/volts are fine. I live in Tampa, FL. It can get chilly enough to need preheat (especially at night) but the engine isn't in freezing conditions.

That’s controlled by the PCM, not the relay. It’s also normal and irregular how the truck performs. Several discussions on here about it.

You really don’t need to wait for the WTS to do its thing in temps above 20°F, just press the button twice and bypass it. That’s better for your batteries anyhow.

 

[Lady_Violet_XXI]

I

That’s controlled by the PCM, not the relay. It’s also normal and irregular how the truck performs. Several discussions on here about it.

You really don’t need to wait for the WTS to do its thing in temps above 20°F, just press the button twice and bypass it. That’s better for your batteries anyhow.

Are you saying that if the preheat cycle starts when it's not particularly cold (like 50-60° F), I should press Start a second time right away, instead of waiting for the autostart after it cycles? Right now, if I try to interrupt it with a second push, it just cycles again. Or it goes into ACC mode. I won't know what's "normal" for my truck until this is all resolved, then I can try your suggestion.

 

[AH64ID]

I

Are you saying that if the preheat cycle starts when it's not particularly cold (like 50-60° F), I should press Start a second time right away, instead of waiting for the autostart after it cycles? Right now, if I try to interrupt it with a second push, it just cycles again. Or it goes into ACC mode. I won't know what's "normal" for my truck until this is all resolved, then I can try your suggestion.

Sounds like your foot is not on the brake if you get a 2nd cycle or go into ACC mode.

I bypass the WTS even if it’s 20°F out.

Press/hold the brake, press the start button, press it again. Truck should start.

 

[Lady_Violet_XXI]

Buy a battery tester on line . Not expensive and very easy to use . you can run battery life , volts ,cold cranking amps etc . Saves you much time money and frustration when trying to figure out if they are good or bad .

I'm going to get one no matter what. At this point I feel like it's a basic tool I should have.

 

[downsc123]

Sounds like your foot is not on the brake if you get a 2nd cycle or go into ACC mode.

I bypass the WTS even if it’s 20°F out.

Press/hold the brake, press the start button, press it again. Truck should start.

just out of curiosity, why do you bypass the intake air heat up when its cold out - also did it start hard when you do that and its below 20F out?