Wiring 69 Key Ignition to 6.4 Hemi PCM Question

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  1. 68RTX

    68RTX Well-Known Member

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    Rookie builder question... Getting ready to fire the 6.4 crate motor for the first time.
    (just doing a mock up to start the motor)
    want to double check the ignition wiring (factory switch to factory PCM)

    How does this "rough" schematic look? - the manual is pretty thin technically and the support line took me to some dude running a boat repair shop. [​IMG]


    Ignition Wiring.jpg
     
  2. Cudazilla

    Cudazilla Active Member

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    Hi, I have a question. Is this the crate hemi plug n play harness or is this a different harness. I have a few pics of the instructions to help out with the fuse requirements. Screenshot_20190417-191740.png Screenshot_20190417-191708.png
     
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    • Cudazilla

      Cudazilla Active Member

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      Also the pink and brown wire needs power while cranking. So I think on most factory igniton switches on these mopars, when in crank mode, the ignition wire loses power. So if not wired correctly it will crank but no start. You can install a time delay relay, like one from a dome light circuit and it can provide power for 3 seconds while cranking and when started, your key will be in run position and maintain power while running. I hope I didn't confuse you, you can google 12v time delay relay and you can see what I'm talking about.
       
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      • 68RTX

        68RTX Well-Known Member

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        I am using the hemi crate plug n play... exactly like you pics. I have the manual just like your pics show.
        This is very helpful sir. Not confusing at all!
         
      • 5.7 hemi

        5.7 hemi FBBO Gold Member FBBO Gold Member

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        If you still have factory wiring in the engine bay, by pass the ballast resistor and solder in a regular wire, now you’ll have 12volts at run and crank.
         
        Last edited: Apr 18, 2019
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