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Truck will not shut off with the key

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by JeffreyG, Feb 25, 2003.

  1. JeffreyG

    JeffreyG Registered Member

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    I have changed from an external regulator to internal regulator I have a problem now the truck wont shut off I replace ignition switch . Is it Something in the wiring also a new alternator???
     
  2. '72brett

    '72brett 1/2 ton status

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    hmm, need more info, any engine mods? is it running strong, or weak?
     
  3. JeffreyG

    JeffreyG Registered Member

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    Engine runs great once it is started there where no other mods since I changed alternator
     
  4. jeffro

    jeffro 1/2 ton status

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    I'm just throwing an educated guess in here but it sounds like the wire for the alternator light is hooked up to the ignition and not the light. If it's a later model like mine there is a single wire from the little plug on the alternator that should go to the alternator light.
     
  5. '72brett

    '72brett 1/2 ton status

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    the lat. light is sometimes called a "dumby" light as I have heard it called. The alt. will not charge unless it receives an initial charge from the battery. This is why the dumby light is used. It lights when it is not charging, but as soon as it starts, it will shut off. The light serves 2 purposes then. Start the alt. and also show you when the alt is not charging. If you do not have the light wired right. and the alt. is hooked up right to the ign. it will still charge, but when the key is turned off, the alt. is still charging your ign. system and will by pass the switch and will in turn, keep the engine running.
     
  6. Burt4x4

    Burt4x4 3/4 ton status

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    Well when you turn the key off it should kill the power to your coil/ignition. If it doesn't then the motor won't recive any change when you turn the key so it stays running.
    Is it possable you wired the ignition to an 'allways hot' side of your fuse box?
    I swaped to a one wire alt and didn't do anything to the old regulator and all my junk works?? I doubt it's the alt "keeping" the motor running...
    my .02.5c /forums/images/graemlins/thumb.gif
     
  7. Steve_Chin

    Steve_Chin 1/2 ton status

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    A shorted diode in the alternator might cause this situation. Have the alternator checked.
     
  8. ntaj*ep

    ntaj*ep 1/2 ton status

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    A shorted diode, or incorrect wiring maybe to blame. Does the truck have any type of ignition box? ie. MSD, Mallory, ect...
     

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