Battery change leading to CEL and transmission control issues.

[RamSport2018]

I own a 2018 Ram 1500 with the 5.7L with the 8 spd, after changing the battery. I drove the truck the day before everything went awry, went to start it up the Sunday to get gas for work, no start. Everything lit up per normal use checked battery with volt meter was low, as it was an original battery to the truck decided it was time to just replace. Replaced the battery, go to start it up, and CEL come on. Had a transmission control code, which went away after and didn’t come back. I choose not to drive it and take my other truck because I baby the ram.
Today I go to check the connections again, and start it up and now it’s acting like it has an aggressive cam (it is stock beyond a lowering kit). The CEL flashes, code states cylinder 7 misfire and ignition issue and won’t shift into any gear only has park and neutral. I can find anything wrong with it wires, coils and spark. It didn’t have any of these issues until I replace the battery, the only thing wrong before was the standard hemi tick from the exhaust, I don’t know what to try next. This truck is the first real truck I bought for myself. I am considering having it towed to a dealer to see if it’s a programming issue, however any guidance would be appreciated. The dealer would be my last resort, I can’t really afford to pay someone else or justify it when I rebuild 80s gm vehicles and any year Saab. The electrical in these vehicles now a days is beyond my capabilities at best. Thanks!

 

[Barr2255]

Check your grounds, bad ground can cause some goofy things. If all checks good, you can try swapping coil packs and see if the misfire follows the coil pack.

 

[LeeD]

Since you didn’t have these issues before the battery change I would try disconnecting the new battery and tie the positive and negative cables together for an hour or so. This should discharge the electrical system. Then hook it back up and see what happens. I’ve had to do this several times on my daughter’s Nitro when it would get wonky.

 

[ExpressRules]

I also advise you should disconnect the battery to clear the system and make sure the battery posts and terminals are tight and clean on reconnection. I'm betting it will return to normal after doing this.

 

[62Blazer]

General rule of thumb......if the truck runs fine, you replace a part or do something to it, and now it has issues.....most likely the issue is related to what you just did. Double check your work. Make sure the battery cable connectors are actually tight and there is no corrosion on anything. If the battery cables have corrosion they can maintain connection on the old battery, but after you remove them and try to reinstall you are getting low voltage. Look around for any cables around the battery that might have accidentally gotten pinched or knocked loose. And just because something is new doesn't mean it's good. Check the battery condition again and make sure it's fully charged. In the end, unhook the battery and reconnect and see what happens.

 

[Barr2255]

Probably worth checking your fuse box as well. I plugged my battery in the other day after a repair and it randomly fried my cigarette lighter fuse.

 

[RamSport2018]

Thanks for the replies I did the battery trick, fixed most of the issues, however the transmission is shuttering after 1st gear and in reverse. Fuses look good, coils are working properly now, I'm gonna say that I got a bad battery, my significant other also replaced the battery in the Cadillac (same battery at the same time), and it was a no crank no start after one day.

 

[turkeybird56]

Yup bad off the shelf. Also helps when you get home 1st night unhook cables and put a charger/maintainer on overnight to get SOC to 100%.

After keeping cables off long time all modules have to resynch, talk to each other and tranny have to relearn.

May Take multiple drive cycles for all to get back to normal.

 

[kwill]

It is good practice to have the new battery tested before you leave the store. I've done this at O'Reilly's and had to reject the first battery they brought out.

 

[RamDiver]

I'm with 62Blazer & TB56.

If everything was OK before you changed parts, additions, or tweaked anything and now it's suddenly failing, don't waste time looking at anything but the changes you've made recently.

Find, borrow, or buy a toaster-style battery load tester such as this one for $20 from HarborFrieght. Don't let anyone convince you that a digital battery load tester will accurately diagnose a flakey cell because that's a total crap shoot.

https://www.harborfreight.com/automotive/battery-tools-accessories/testers-tools-accessories/load-testers.html

While you're there, pick up a $3 battery post/clamp cleaner too.

Battery Terminal Cleaner

Amazing deals on this Battery Terminal Cleaner at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

And, to Ram Forum.

.

 

[LouM]

When I had the battery in my "19" go I used a boost pack to get it started and all was fine. The next time it was dead and I tried to start it. I got all kinds of alerts, alarms and codes scrolled accros the dash. After I replaced the battery it started fine and seemed normal I drove down my driveway to the road and it would not shift out of first gear and would not engage 4wd. When I got it home and used a code reader it has several communication errors stored, including transmission and body control modules, after clearing those everything came back to normal.

 

[RamDiver]

When I had the battery in my "19" go I used a boost pack to get it started and all was fine. The next time it was dead and I tried to start it. I got all kinds of alerts, alarms and codes scrolled accros the dash. After I replaced the battery it started fine and seemed normal I drove down my driveway to the road and it would not shift out of first gear and would not engage 4wd. When I got it home and used a code reader it has several communication errors stored, including transmission and body control modules, after clearing those everything came back to normal.

After a recent battery disconnect on my truck, I've realized that our trucks behave very much like a PC that loses power suddenly and without a proper shutdown process.

AFAIK, the Ram Engineering folks never bothered to consider a shutdown process and we're just hard stopping these rolling computers and not anticipating creating any module communications faults, that's an error.

The BCM module lost connection to peripherals and other modules on my truck and required a restart/reset.

Fortunately, it was a tech at the dealership who failed to test my truck after disconnecting/reconnecting the battery.

Another SA immediately recognized the issue, plugged in an interface into the OBD2 port and restarted the BCM.

Gone are the days of a simple battery change, now every module has to reacquire connectivity before normal operations can progress.

.

 

[Marshall]

just thinking out load, I wonder if a power pack across the cables when changing a battery would stop some of this?
I picked up a battery one time and the dealer blow dust off it, it sat for 3 yrs , I made him load test it, he said its' new" it tested at 50%. Some poor bugger would have bought that, but it was not me.

 

[Panduh]

just thinking out load, I wonder if a power pack across the cables when changing a battery would stop some of this?
I picked up a battery one time and the dealer blow dust off it, it sat for 3 yrs , I made him load test it, he said its' new" it tested at 50%. Some poor bugger would have bought that, but it was not me.

That's what I just did with my 2016. No issues whatsoever - even the clock was good.

 

[62Blazer]

Sometimes you will get crazy codes and such when swapping batteries, but that is not the norm. I've swapped dozens of batteries on newer vehicles and have never gotten any codes or warning lights. Swapped batteries in my '16 last year in the Walmart parking lot with zero issues. Sure, it can happen sometimes....but just sometimes.

 

[Dusty]

just thinking out load, I wonder if a power pack across the cables when changing a battery would stop some of this?
I picked up a battery one time and the dealer blow dust off it, it sat for 3 yrs , I made him load test it, he said its' new" it tested at 50%. Some poor bugger would have bought that, but it was not me.

Yes, it probably would have. This is typically done in auto repair shops nowadays.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 122412 miles.

 

[Wild one]

Then there's me who is always disconnecting the batteries,and the only one that has to sit was the 2019 Challenger.It needed to sit about an hour with "no" key cycles before it got the drag pages /linelock etc.back.
Hell everytime i parked the truck and knew it was gonna sit for more then a day or 2,i turned it's master disconnect switch off,which killed battery power,throw in the fact everytime it was at the track the master disconnect got checked to make sure it shut the truck off while it was running.
I've also helped out alot of late model Mopar owners reset the adaptives at the track by disconnecting the battery in their trucks and cars,and never once has it bit me in the rear
You guys sure seem to have alot of trouble with disconnecting batteries,makes me wonder what in hell you're doing wrong,lol

 

[LouM]

Then there's me who is always disconnecting the batteries,and the only one that has to sit was the 2019 Challenger.It needed to sit about an hour with "no" key cycles before it got the drag pages /linelock etc.back.
Hell everytime i parked the truck and knew it was gonna sit for more then a day or 2,i turned it's master disconnect switch off,which killed battery power,throw in the fact everytime it was at the track the master disconnect got checked to make sure it shut the truck off while it was running.
I've also helped out alot of late model Mopar owners reset the adaptives at the track by disconnecting the battery in their trucks and cars,and never once has it bit me in the rear
You guys sure seem to have alot of trouble with disconnecting batteries,makes me wonder what in hell you're doing wrong,lol

I don't think it is anything being done wrong. I suspect that in mine it was because I tried to start it with the low battery and the voltage sag to almost zero threw every thing out of kilter, I reset mine with a code reader. I try not to travel without a code reader in the vehicle.

 

[Wild one]

I don't think it is anything being done wrong. I suspect that in mine it was because I tried to start it with the low battery and the voltage sag to almost zero threw every thing out of kilter, I reset mine with a code reader. I try not to travel without a code reader in the vehicle.

Could be i guess,although i've had a few times where i've had a neighbours mopar product need a boost,as it doesn't have enough juice to start,and have never really had any issues to speak of with codes afterwards.
I agree i keep a cheap $20 code reader in everything i own.

 

[Sherman Bird]

I own a 2018 Ram 1500 with the 5.7L with the 8 spd, after changing the battery. I drove the truck the day before everything went awry, went to start it up the Sunday to get gas for work, no start. Everything lit up per normal use checked battery with volt meter was low, as it was an original battery to the truck decided it was time to just replace. Replaced the battery, go to start it up, and CEL come on. Had a transmission control code, which went away after and didn’t come back. I choose not to drive it and take my other truck because I baby the ram.
Today I go to check the connections again, and start it up and now it’s acting like it has an aggressive cam (it is stock beyond a lowering kit). The CEL flashes, code states cylinder 7 misfire and ignition issue and won’t shift into any gear only has park and neutral. I can find anything wrong with it wires, coils and spark. It didn’t have any of these issues until I replace the battery, the only thing wrong before was the standard hemi tick from the exhaust, I don’t know what to try next. This truck is the first real truck I bought for myself. I am considering having it towed to a dealer to see if it’s a programming issue, however any guidance would be appreciated. The dealer would be my last resort, I can’t really afford to pay someone else or justify it when I rebuild 80s gm vehicles and any year Saab. The electrical in these vehicles now a days is beyond my capabilities at best. Thanks!

You cannot just replace the battery on that truck. You must calibrate the battery to the truck. You must have a scanner with AutoAuth capabilities to do this and clear the DTC's.