2025 RAM 1500 BIGHORN 3.0 I HURRICANE twin-turbo, SO, 420HP - check engine light

[KevInSD]

I'm about 3600 miles in now and no CEL. I do have very hard & some jerky shifting though. Also it sounds like it misfires on cold starts.

I do have some odd things like BSM showing I have a trailer connected randomly and then turning off after a few seconds.

My start stop function does some weird things too. At night when it comes time to start the truck sometimes it will turn off all the exterior lights and turn back on when the truck starts. Also odd is that if I come to a complete stop and it shuts the engine off sometimes I can shift to park while still holding down the brake pedal and it will stay in shutdown mode until I let go the pedal then it will restart. My Jeep will not do this, once I shift from drive to neutral it will turn on no matter what, my 21 Ram did the same.

Last issue I have is the exterior lighting. All my exterior lighting will light up during the day, headlights & puddle lights on the side mirrors and rear tailgate handle. At night the headlights don't light up ever! So if I park in reverse I can't tell where my truck is by the headlights at night.

Apart of those things, I get about 20mpg on average in city and hwy drives. Last week I did nothing but city driving, which is a tenth of a mile every day, to go take my dog to the park now that the kids are back to school and my mpg is about 15.

Today when driving around town I felt like my transmission "stuttered" when taking off. I was always used to my 2019 have a delay when taking off from a stop but this is more of a stutter. It's something I'll definitely be keeping an eye on.

 

[Cbty2050]

They definitely know about this problem but nothing is getting resolved

They know about it, they are working on it. Everyone assumes software issue. These things take time and have multiple hurdles to get it out. Can't just release an update that may mess up emissions compliance.

 

[JimfromAZ]

Same misfire issues with mine. Still waiting on Ram for a fix. They definitely know about this problem but nothing is getting resolved

How obvious are the misfires?

 

[Finnyatf]

How obvious are the misfires?

At cold start it misfires but it’s most noticeable cruising around 40mph when rpms are at 1000-2000 rpm. It misfires and stutters but higher than 2000 rpm its fine…

 

[Whoa_Ram]

That's one thing my start stop hardly ever activates, I'm not complaining just odd, the message always says climate control cooling. Will see what happens once the temperatures cool off a bit.

Very odd, it's been above 100 these last few days here in Texas and mine will activate after cooling down for about 10 mins.

 

[Whoa_Ram]

How obvious are the misfires?

Cold starts for sure are super noticeable for sure. I'll have to try cruising around 40mph as Finnyatf mentioned to see if I notice them too.

 

[Biga]

Yea, today was the first cool morning and I turned the AC off and

Very odd, it's been above 100 these last few days here in Texas and mine will activate after cooling down for about 10 mins.

Yes, today was the first cool morning, and I turned the AC off. The start stop was activating with every stop with it off, I guess mine does not like to activate with the AC on for some reason. I don't usually blast the AC either.

 

[Whoa_Ram]

Yea, today was the first cool morning and I turned the AC off and

Yes, today was the first cool morning, and I turned the AC off. The start stop was activating with every stop with it off, I guess mine does not like to activate with the AC on for some reason. I don't usually blast the AC either.

I usually run mine on Auto mode at 73 degrees. On my wife's Jeep Grand Cherokee it never activates during the summer and maybe a handful of times during the winter lol

 

[azzx]

My start/stop activates 99% of the time. I turn it off the moment I start the engine - too hot in AZ not to have AC at every stop!

 

[swine]

Got the CEL shortly after delivery at 15 miles. Turned out to be codes P0E78 (coolant bypass valve) and U063B (generic network fault). Local dealer ordered the parts and it goes in for repair on the 3rd.

 

[OutKartnAround]

Cold starts for sure are super noticeable for sure. I'll have to try cruising around 40mph as Finnyatf mentioned to see if I notice them too.

We have identical issues. Mine has been with the dealer since last Friday. I’ve been enjoying the 10mpg the gasser 2500 loaner has been getting 🙄

 

[Whoa_Ram]

We have identical issues. Mine has been with the dealer since last Friday. I’ve been enjoying the 10mpg the gasser 2500 loaner has been getting 🙄

Did yours give you a CEL?

 

[Dex17]

Just bought my 1500 Laramie with the standard output this past Saturday. Only issue I had driving it off the lot was that the 'Service Trailer Break' came on (no CEL tho). Dealer looked at it but couldn’t diagnose why that was appearing. Try to use the trailer break and nothing happens. I don’t haul or trailer anything so I’ll get it fixed when Ram has a solution.

Another thing I noticed is this engine loves to run in the 1500-2000rpm range even when warm when first started. Takes about a minute to wind down to below 1000rpms.

Also when idling the engine will rev up and down for about 5 secs then evens out. Happened twice when idling for about 10 mins. Happens everytime though if idling for about 5 mins. No CEL tho and the engine runs smooth when driving. Don’t know much about this engine though so not sure if that’s normal or not for it

 

[ESL12]

Just bought my 1500 Laramie with the standard output this past Saturday. Only issue I had driving it off the lot was that the 'Service Trailer Break' came on (no CEL tho). Dealer looked at it but couldn’t diagnose why that was appearing. Try to use the trailer break and nothing happens. I don’t haul or trailer anything so I’ll get it fixed when Ram has a solution.

Another thing I noticed is this engine loves to run in the 1500-2000rpm range even when warm when first started. Takes about a minute to wind down to below 1000rpms.

Also when idling the engine will rev up and down for about 5 secs then evens out. Happened twice when idling for about 10 mins. Happens everytime though if idling for about 5 mins. No CEL tho and the engine runs smooth when driving. Don’t know much about this engine though so not sure if that’s normal or not for it

I had this same service trailer break message that started around 300 miles. I called the dealer they said it just needs to be turned off and to come in. I figured I’d just wait till I needed to go in for something oil change etc. at 1300 miles I got the misfire and CEL. So I bring it in tell them about both. They claim they couldn’t reproduce the service trailer message even though it was every start up for 1000 miles. My misfire issue they claim was my ignition control module which they replaced and cleared the codes. Now I wait for my eventual CEL again. I’ve already seen misfire codes in my scan without CEL. So time will tell.

 

[Rambo25]

Update on mine. After 2 weeks and a lot of aggravation with poor customer service and having to fight for a loaner/rental. My dealer miraculously got the part that was back ordered with no eta that they claimed caused my issue. Ignition Control Module. I’m picking it up this afternoon. Fingers crossed this is the end of it but I’m leary. It seems everyone with this issue is getting different repairs. And many still have the issue afterwards. I’ll update once I have a few hundred miles on it. Good luck all!

ESL12, Did the ICM change help/fix the misfire issue?

 

[a3vr]

I had this same service trailer break message that started around 300 miles. I called the dealer they said it just needs to be turned off and to come in. I figured I’d just wait till I needed to go in for something oil change etc. at 1300 miles I got the misfire and CEL. So I bring it in tell them about both. They claim they couldn’t reproduce the service trailer message even though it was every start up for 1000 miles. My misfire issue they claim was my ignition control module which they replaced and cleared the codes. Now I wait for my eventual CEL again. I’ve already seen misfire codes in my scan without CEL. So time will tell.

I had the service trailer light that I associated with me playing with the trailer brake controller with no trailer hooked up. But plugging and unplugging the trailer solved it. Now I *almost never play with the brake controller

 

[OLLIECB]

Update on my CEL misfire issue...so far so good. Put a few hundred miles on her and the fuel pump replacement has been the answer (I hope that didnt jinx me). Sounds like a lot of different solutions given for the same CEL misfire problem on this thread. I hope everyone gets some resolve.