Strange No-Start

[TLane]

I frequently hear from diesel truck owners that "they can't believe that both batteries went bad at the same time. " The answer is, they don't. But our trucks will start and run under most circumstances with just one battery. So if one battery gets weak, as long as it doesn't short and drain the other battery, everything will work just fine. That is, until the other battery goes bad, at which point you have two bad batteries.



In addition, the two batteries in your truck were most likely made by the same manufacturer, on the same assembly line, using the same process, one right after the other by the same operator. If one goes bad, how long do you think it will be until the other goes bad?



I'm not saying that's what happened in your case, but it happens a lot more often than people realize.



Charge the batteries individually, get them load tested, and then you'll have some information to go on. If one is bad, it's best to replace them both anyway.

 

[BHiggins]

I know it's possible, I'm just saying I feel it's unlikely. Both of them are dead dead, ZERO volts dead. Not even enough juice to illuminate a test light dead. Deader than Abe Lincoln dead. It's been my experience that when a battery (or BOTH batteries) go bad, there's usually a volt or two left in there. They'll usually be enough juice left to at least make the solenoid click, or the interior light go on, or the horn honk, or SOMETHING to work even a little. I'm not exaggerating when I say they won't even turn on a 12v test light... I did hook up cables to the driver's side battery tonight, I was hoping to see that I had left something on that would explain the sudden death, but nothing was left on. Right now I have the batts disconnected, and a charger on the passenger battery. In the am, I'm hoping the one battery will be somewhat charged, so I can either switch the charger to the drivers side, or hook cables to the drivers side just to get it running and up to the dealer.

 

[jelag]

Brian...

They(batteries) are connected in parallel, if one runs down from a draw, they both will be down and have no power. . its a simple matter of ohm's law... These batteries are between 100-120 amp hour batteries... a 10 amp charger will take 10-12 hours to recharge one from being flat to fully charged... a 5 amp charger twice that time... (X2 for 2 batteries)

I just retired and closed my business... but, because of my insecurities with the dealer have taken steps to understand these trucks and deal with my issues... .

When I was selling equipment and installing it, the guy who trained me was a mechanical and electrical engineer trained during and after WWII, the one statement he left me with was to always understand the theory of operation, and than work to understand whats wrong... . Than TEST don't GUESS..... 35 years later, his simple words always come to mind and that is what drives me... .

There is not a lot of difference in the starting, charging circuits on this truck from your 1st gen truck...

What does surprise is that one of the features of the new trucks is sensor that will shut down draws that the computer can see when the engine is off...

I seem to have ruffled your feathers, for that I'm sorry... . The direction your taking is very different than the one I would work towards... I'm going to leave this post to the rest of you...

 

[BHiggins]

Jim, no ruffled feathers, believe me... It's just frustration at the truck, not from anything you said. This is my third Cummins/Dodge, and the last two combined didn't give me as many problems as this truck. The other two trucks had a combined mileage of over 445,000 miles and neither one EVER FAILED TO START, even once. This truck has less than 25k on it, and this is the third time it's let me down (not to mention already being back at the dealer twice for factory recalls already). As much as I love the Dodge/Cummins partnership, I'm beginning to question my choice this time... Three no-starts and two recalls in less than 25,000 miles, maybe I should have bought a Chevy.

 

[BHiggins]

Update: I hooked a charger up to one battery last night, and left it on for a good 12 hours. This morning, I hooked cables up to the other battery, and the truck fired right up. I drove the truck for about an hour (as you guys stated earlier, drives are measured in hours here in NY, not miles), and everything seems to be ok. When I got home, I isolated both batteries again, and hooked a second (borrowed) charger up. Now I have both batteries on separate trickle charges, where they will stay for the rest of today. Once they are both fully charged, I'll test them and go from there.

 

[BHiggins]

I'm a big enough person to admit when I'm wrong... You guys were right, it was JUST the batteries.