Won't start unless I jump it

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^ I was about to post this before I read your comment. Remember it's the entire conductor that has to conduct current, not just the end connectors. Someone I know recently had an electrical fault that was traced to internal corrosion in a ground cable. It wasn't positively located until the insulation was stripped off the cable and visually verified, but the ohmmeter showed the fault.

Just for grins, what's the resistance in your main ground cable and the positive lead directly to the battery?

Unfortunately resistance testing can be deceiving . You could have 1 good strand of copper left in a cable, and a multimeter could show 0 ohms because it's only sending microamps for testing. However, you send any actual current through that cable and it would have a huge voltage drop.

What OP needs to do is measure the actual voltage drop when cranking. Put the positive test lead on the positive battery post, and put the negative test lead on the starter positive cable post (the other end of the cable). Try to crank the engine and write down the voltage reading while the key is turned to the start position. This will tell you the voltage drop on the positive wire.

Repeat the same procedure, but put the negative test lead on the solenoid wire at the starter. This will be the solenoid circuit voltage drop.

One last repeat, but this time put the positive test lead on the starter body, and the negative test lead on the battery negative post. That will be your ground cable voltage drop.

My money is on one of those pieces of the starter circuit has excessive voltage drop/corrosion/damage.
 

Njck22

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If jumping works right off the battery posts my intuition tells me the heavy guage cabling is not the issue. does no harm to go ahead and measure the voltage drop, though
 
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Thanks. I’ll take a look tonight. Does anyone recall the vendor here that sells those battery cable kits? I bought one from him back in 2017. It seems to be pretty good quality. Maybe I have a nick or short that I cannot see. I recently moved to the country so maybe a little critter has been active in my engine bay. I appreciate all the feedback. I’ll get my tester out and take some readings.
 
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Thanks. I’ll take a look tonight. Does anyone recall the vendor here that sells those battery cable kits? I bought one from him back in 2017. It seems to be pretty good quality. Maybe I have a nick or short that I cannot see. I recently moved to the country so maybe a little critter has been active in my engine bay. I appreciate all the feedback. I’ll get my tester out and take some readings.
A set of long retractable test leads works great if you leads aren't long enough. Especially if you're by yourself, you can run the DVOM inside the truck to watch it while you crank.
 
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@jasheehan I would first try jumping from the battery positive terminal to the starter's 12V switched input. You might have a little bit of resistance in the long series of contacts that supplies power to the starter input. Just enough resistance that the ~12.8V of you battery can't push enough current to activate the solenoid (plunger), but the ~13.x - ~14.x of a running vehicle can.

 

Njck22

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Test if the starter engages you give it 12v directly to the solenoid spade connector.

The voltage drop problem could actually be elsewhere, the source of your voltage drop most likely is in your remote starter, which interrupts the solenoid wire coming off your ignition switch under the dash. That whole remote starter system has probably built up some resistance over 12 years. A 14.8v jump from a running car overcomes that, but without that the click you’re hearing is just the relays or the solenoid partially engaging.

The optimal fix is to refresh all that remote start stuff. The other option is to add a relay on to the solenoid wire at the starter
 

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