So I'll start by apologizing for having my first post be a cry for help, but that is pretty much where I'm at. I stumbled upon this forum while doing some research and to get you up to speed, about a month and a half ago I traded in my 2015 Silverado 1500 that ran perfectly fine for what I thought was a good deal on a 2010 MegaCab with a 6.7 that had been deleted, had aftermarket Headstud's, with an H&S Mini Maxx tuner, so about a week an a half of driving it occasionally around town dropped the youngest one off at school and came back top the house to grab something and went to leave and the truck was completely dead, no power at all. I get to looking and the drivers side Positive terminal clamp was beat to hell, cracked, and corroded pretty bad, so I clean them up, jump it off and drive it to the parts store and put a pair of new batteries in it and everything is fine. 3 days later I am driving through town and the radio cuts off, lights and whole dash start flickering and it starts sputtering then loses all power and luckily roll up to my friends driveway. I get it towed home,2 weeks later have a new mil spec bolt on clamp with a ring post made for the Positive cable, the one that runs to the starter solenoid, and put it all back together then go to jump it. The truck powered up and everything was normal on the dash, the Voltage indicator dropped slightly while cycling the plugs, but once it cycled it went right back up to almost 14V but it would never turn over. It sounds to me like the bendix is engaging but it's just not firing at all. I have the batteries hooked up to a charger right now, but what else in the world could it possibly be? By power of deduction I don't think it's the alternator, the fuses look good, and the connections are good so I am stumped. I appreciate any and all help, and apologize for being long winded but I figured you'd want as much info as possible to help troubleshoot as I am about as green as a gooseberry when it comes to Diesel's.

 

Many Thanks,

Levi

Welcome to the forums, 

so you are saying the truck cranks over just fine but isn't firing off correct? first check for codes, i'm sure the Mini max does this. we need to know if there is any. 

Next does the mini max show Rail pressure? We need to know this while cranking. the computer needs to see around 5K to fire the injectors. i think you might try reflashing the computer with the mini max. i think the mini max can load custom tunes as well. might research your to see if it's the stock minimax or someones custom ones. 

Let see if I understand what your saying.   When you turn the key you can here the starter solenoid snapping the bendix  into the ring gear but the starter motor is not turning the engine over?

 

If this is the case then with fully charged batteries check the cranking voltage with a volt meter when the key is turned to start.  The battery voltage should drop to ~11.5V when the starter is running then come back up to a rest voltage of ~12.5V . 

If there is no drop in voltage then check for a bad/loose connection at the solenoid terminal of the strap that goes into the starter. I have seen the terminal nut that holds the strap/cable to the solenoid come loose.  This is not the cable from the battery to the starter.

You can test for voltage at that terminal also.  If you have voltage there when the key is turned then you have a bad starter.  If you have no voltage there with the key turned and the solenoid moving the bendix then the contacts in the solenoid are bad. 

    

 

1 hour ago, Killer223 said:

Welcome to the forums, 

so you are saying the truck cranks over just fine but isn't firing off correct? first check for codes, i'm sure the Mini max does this. we need to know if there is any. 

Next does the mini max show Rail pressure? We need to know this while cranking. the computer needs to see around 5K to fire the injectors. i think you might try reflashing the computer with the mini max. i think the mini max can load custom tunes as well. might research your to see if it's the stock minimax or someones custom ones. 

It does not crank at all, just resets the electronics like the battery doesn't have enough to jump it, but each battery was hooked to a running vehicle and it still wouldn't jump , so I'm charging them now even thought they're only 3 weeks old.It has the Stock, Tow, Street, and Performance tunes but I met the old man that owned it and he had taken relatively good care of it and didn't really beat on it too bad, just got to where he couldn't take care of it. I'll get out there tomorrow and check the tuner for Codes and also do some troubleshooting with a multimeter now that I have familiarized myself with the Starter and Solenoid then get back to you. Thanks again

1 hour ago, IBMobile said:

Let see if I understand what your saying.   When you turn the key you can here the starter solenoid snapping the bendix  into the ring gear but the starter motor is not turning the engine over?

 

If this is the case then with fully charged batteries check the cranking voltage with a volt meter when the key is turned to start.  The battery voltage should drop to ~11.5V when the starter is running then come back up to a rest voltage of ~12.5V . 

If there is no drop in voltage then check for a bad/loose connection at the solenoid terminal of the strap that goes into the starter. I have seen the terminal nut that holds the strap/cable to the solenoid come loose.  This is not the cable from the battery to the starter.

You can test for voltage at that terminal also.  If you have voltage there when the key is turned then you have a bad starter.  If you have no voltage there with the key turned and the solenoid moving the bendix then the contacts in the solenoid are bad. 

    

I appreciate the point in the right direction, I just familiarized myself with their respective layout and a general understanding of the starter/Solenoid relationship and their contacts, so I'll keep narrowing it down from here. If anything, I might just yank the starter out and do a thorough cleaning and inspection of the contacts and plunger while waiting on the rebuild kit to arrive. It'll need to be done eventually I guess..

 

I wonder if the contact is shot on the starter. That would produce the Bendix popping out for the flywheel but not power for the starter motor to turn the flywheel. 

 

Welcome to the site. Ask plenty of questions. We'll all try to help you out.

Hey guys, I appreciate all the help, after troubleshooting with a voltmeter and testing a few options it turned out to be the alternator had crapped out and the batteries had drained pretty significantly. Got them both charged up good and replaced the alternator, so we are back in business. Very good learning experience, and I found this forum in the process so Thanks again.

Thanks for reporting back in with your findings. I would still have the batteries retested to be sure your not stressing the alternator with weak batteries.

1 hour ago, Mopar1973Man said:

Thanks for reporting back in with your findings. I would still have the batteries retested to be sure your not stressing the alternator with weak batteries.

I did go ahead and have them tested at Advance when I took the alternator up there to have it tested and pick up the new one, so I feel confident I covered *most all of my bases. They are practically brand new, as I replaced the pair that were in it right after I bought the truck and it died the first time. So my guess is, and correct me if I’m wrong, but the bad alternator was contributing to the batteries draining down and not recovering. When I jumped it this morning it ran fine for a short while then the voltage dropped and it sputtered out which lead me to the alternator . There were a ton of voltage related codes on the Tuner so tomorrow I am going to clear them and put it through it’s paces and take it for a test drive. 

Alright, got her buttoned up and running like a top. The drivers side battery still wasn't holding a charge good so I went and swapped it out under warranty(1 month old) and once I dropped the new battery and alternator in it she fired right up and everything seems to be as it should. There's a lesson in everything I guess, and troubleshooting know how is probably one of the biggest I have learned to keep from making dealership owners richer. Thanks again and look forward to seeing you guys around.

22 hours ago, Mopar1973Man said:

I would still have the batteries retested to be sure your not stressing the alternator with weak batteries.

 

I'm going to bet the other battery is weaken too. Batteries should be swapped as pairs.

Edited January 14, 20187 yr by Mopar1973Man

12 minutes ago, Mopar1973Man said:

 

I'm going to bet the other battery is weaken too. Batteries should be swapped as pairs.

I did replace them as a pair not even a month ago, and the passenger side tested fine, so just the drivers side was bad. 

Ok. That short of time you might be fine. If it tested good then you should be fine. 

37 minutes ago, Mopar1973Man said:

Ok. That short of time you might be fine. If it tested good then you should be fine. 

Ten fo, that’s what I’m hoping