2015 Laramie not turning over

[JCJohnson]

Guys, drove my Maxi cab on Tuesday went out to start it Wednesday morning it wouldn't turn over. It was very cold and not plugged in. Won't turn starter, 12.3 volts at batteries still connected together. Shouldn't that be enough? What should I be looking for? It doesn't click or even turn the starter. Arg! Fuse? Relay? It's dark and cold. So maybe tomorrow.

 

[DHayden]

12.3 may be low for very cold. Do the interior lights dim when you try to crank? (even if it doesnt turn over)

 

[JCJohnson]

Dash board and interior lights are bright. No starter? No turning of starter.?

 

[DHayden]

I would check the connection from battery to starter. You can put jumper cables straight to the starter, if it doesnt crank or at least make noise the starter is probably toast.

 

[gsbrockman]

Guys, drove my Maxi cab on Tuesday went out to start it Wednesday morning it wouldn't turn over. It was very cold and not plugged in. Won't turn starter, 12.3 volts at batteries still connected together. Shouldn't that be enough? What should I be looking for? It doesn't click or even turn the starter. Arg! Fuse? Relay? It's dark and cold. So maybe tomorrow.

Load test batteries individually. 12.3 volts won’t tell the true story.

If your truck has OEM batteries.....I’ll bet they’re done.

 

[jhenderson]

I would check the connection from battery to starter. You can put jumper cables straight to the starter, if it doesnt crank or at least make noise the starter is probably toast.

I’d like to see you put cables directly to a 4th gen starter.

Load test them, Properly. $10 says one or both fail.

 

[Deleted member 995608]

It's probably your batteries. My 2016 did the exact same thing a little over a month ago.

 

[DHayden]

I’d like to see you put cables directly to a 4th gen starter.

Thats true, I still think mainly of my 2nd Gen since I've done a lot more work to that one.
His interior lights should at least be dimming or go out when he tries to crank.

 

[Cummins12V98]

I'm betting batteries. My Son's RAM is a 15 also and his died a couple months ago.

 

[jhenderson]

Thats true, I still think mainly of my 2nd Gen since I've done a lot more work to that one.
His interior lights should at least be dimming or go out when he tries to crank.

Without proper voltage and amperage the electronics won’t even try to engage the starter, hence no dimming of lights. Same reason a truck will sometimes crank only a few revs then drop the start sequence.

 

[TRAMPLINEMAN]

Same reason a truck will sometimes crank only a few revs then drop the start sequence.

This is what mine did. Interior lights and dash lights never dimmed. Grid heater light illuminated for maybe a second or two. Truck turned over a couple revs and quit. Batteries were gone.

 

[Ozymandias]

12.3 without load is almost an empty battery.
12.8 would be full.

Cummins starts without Grid Heater or Preheated witn no Problem down to -30°, he doesn't like it but he can.

 

[mhstevens]

I had the same problem on my 2015. $300 and two new batteries later, the problem was still the same. Found that a nut fell off the starter solenoid and was intermittently making contact. At least I have two new batteries...