Hi Pete,
It's okay, we now know it's not likely to be the key or the bend spot on the ignition harness there. It's a start but changing the battery seemed to help for two days or not really. Can I get the engine size that's in it and we can dig a little deeper in your issue. I just want to confirm when you bought the truck this problem already existed, correct. I'm taking it there is no check engine light on. If you can get it scanned anyway maybe their are stored codes in there from the past. A problem that doesn't happen all the time can be a little tricky to identify there are a lot of things it could be. Something like this when it works most of the time leads me to checking for a bad or corroded electrical connection. Has it ever turn off while driving? Try to make it fail, start the car open the hood and while doing a visual inspection of the vacuum lines and wiring start to move wires in there and see if you get any skip, stall or any change at all. Some sensors that have not completely failed can be temperature sensitive, even sensitive to humidity and weather. See about any stored codes and maybe go back in your memory for anything that coincides with the no crank. Both the BCM (Body Control Module)and the ECU (computer) have control in your system. I've attached the wiring diagram for the circuit that's acting up, Sorry about having to split it sometimes we need to, to get it all. Do you have a test light?
Tom
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Wednesday, August 26th, 2020 AT 2:53 PM