600rrpilot

Hey everyone. Had a lil issue a couple weeks back and still cant figure it out. Well first off this all began one early morning at the quarry. I have a dump insert in my 04 3500 cummins. I went to dump concrete and nada....dump doesnt work. i try messing with the solenoid on the pump...nothing. So i emtpy 2000 lbs of concrete by hand and go on my way. Get home pop the hood. The positive post on the secondary battery is fried! wires all melted right off. So i immediately think the dump hookup is shorting out. so i tap it to the terminal..nothing....press the button and the dump works fine. oooook. so then i touch the other lead that goes to the terminal....and bammmm its shorting out. So I needed the vehicle for work....and couldnt figure anything out right away. so i checked the batteries and it seems like while running the alterator was still giving them a charge. So I tucked that lead out of the way and used the truck....no issue. couldnt find out what that lead was in my service manual...its not on the wiring diagram. makes no sense to me.

THEN....my water pump thats been leaking a lil bit decided to let go....soooo...over the weekend I replaced the pump...flushed the cooling system. and repaired a pinhole in the radiator (dont ask). threw on a new serpentine belt that I had sitting around since this stock one now has 116K on it. get everything together....go to start the truck....click click click. Throw on the multimeter...11.4 volts....crank it...down to 2.3 volts. so im thinking to battery is shot. Is original too....5 years old now. so I think i need to replace it anyway...BUT....

does that lead have something to do with the charging system? like i said its on the secondary battery and goes to two solenoid looking things right alongside the battery. does anyone know what this is? and what could be shorting it out?

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grid heater relays

600rrpilot

hmmm....but when i turn the key you can still hear them ticking before i try to start it? does that make sense?