12v feed for ballast resistor.

Electrical & Ignition

  1. furyus 67

    furyus 67 Senior Member

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    I am running a MSD 6AL. For my 12v remote I used the feed for the ballast resistor. But it will not fire the MSD. Any ideas on why? When I have these spliced into the the feed wire I'm getting 12v at my MSD plug. Turn the key off and on and the does what it's supposed to but won't fire the MSD.
     
  2. furyus 67

    furyus 67 Senior Member

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    Could it have anything to do with alternator not charging?(another issue) I've got an optima red too in the car now. I also have the remote wire hooked to a switch so I can start it. Any thoughts?????
     
  3. Yatzee

    Yatzee Active Member

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    There are two positions for the ignition switch, start and run. In the start position power bypasses the ballast resistor and you feed a full 12v down the line. Once started and in the run position, power is restricted to much less than twelve volts. You do not need a ballast with some coils due to the windings so you can twin the wires at the ballast together so you get a full 12v all the time to the coil. Are you sure you should use a ballast resistor with the MSD controller? If so you will need to rewire to ensure that the box itself gets a full 12v when the key is in both start and run separate from the ballast output. Recheck the wiring schematic for the 6AL and run a new fused circuit from the ignition side of the switch. Wiring1.jpg

    Wiring1.jpg
     
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  4. furyus 67

    furyus 67 Senior Member

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    Thanks Yatzee! I didn't realize the voltage bypassed the ballast resistor during the start cycle. I was only using the feed wire for it because it was the closest 12v switch to the MSD. I'll find another.
     
  5. furyus 67

    furyus 67 Senior Member

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    So what's a good alternative 12v switch that isn't reduced during startup?
     
  6. furyus 67

    furyus 67 Senior Member

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    In the engine bay. I've already cut my switch wire coming from the MSD so it's not very long and I'm not a fan of splices.
     
  7. furyus 67

    furyus 67 Senior Member

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    Ok figured that one out. Ended up using the feed on the other end of the ballast. The old coil wire.