Ram 5500 6.7 L full power but not turning over

[WesternKwik]

As the title says, all the accessories in the truck work, the power is definitely there. When I turn the key the I can hear a click like it is trying to start but no actual turning over. It seems to be some weird connection from the starter, to a little box that is connected to a ground. Has wires going from the starter to the box, the battery negative to the box, and from the box into the cab of the truck.

I will include a picture of the box and a weird "splice" in the wire between the box and the starter. Does anyone know what this box is and if it would cause the truck to have these issues?

 

[mtnrider]

Not sure what that abomination of wiring is but it does not look factory?

As far as not starting, you need to load test your batteries individually. That is most likely your problem and I would place my money on that. Just because it reads 12v and the dash lights up doesn't mean anything on these trucks.


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[WesternKwik]

I will try that and post the results here. Thank you for the feedback

 

[WY-Dave]

the "box" is a auto resetting circuit breaker. If you have a volt meter take the black lead to a ground point and then check each of the lugs on the box.
going by its condition it might not reset anymore.

 

[WesternKwik]

I have a multi-meter here and just wondering when/how I would actually test it? As in, does it need to be connected to those wires and then put the black lead onto a ground and test both? I am not even sure what setting I would use for the multi-meter. I just did a load test and my batteries both say 12.49 V.

Would this circuit breaker prevent the truck from starting? It might be positive air shut off. I have it completely out of the truck and every thing seems to be exactly the same inside when I try to start it up.

 

[WY-Dave]

What the circuit breaker (CB) does is interrupt the "hot" (+) line. One side would be coming from the battery and the other would be going to the load. Just think of it as a fuse that resets itself.

To test this take a voltmeter and put it on VDC (below pic usually V with straight lines ), the black lead on a ground, battery neg terminal etc and then the red lead to one terminal on the CB. If the CB is not "open", meaning not connecting the 2 studs) you will have voltage only on 1 of them.




An alternative to the the multi-meter is a test probe, usually <$10 Wally or HF. The black lead will again to a ground (frame, mounting bracket etc) and then the sharp tip will go to the studs on the CB. If there is power, then the handle will light up. These are handy as heck for a quick diagnostic. Reminds me I need to get another one.


Now for the question of "is the problem" going by the wiring, I would not be able to say what circuit the CB is protecting. But it would be part of the process of elimination for the issue.