76 GT4 fuse box upgrade - wiring question | FerrariChat
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76 GT4 fuse box upgrade - wiring question

Discussion in '308/328' started by vidkidruss, Aug 24, 2013.

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  1. vidkidruss

    vidkidruss Rookie

    Jul 13, 2013
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    Russell Harris
    #1 vidkidruss, Aug 24, 2013
    Last edited by a moderator: Sep 7, 2017
    Hi all,
    I'm upgrading my '76 308 GT4 to the wonderful Birdman fuse boxes and I've got a question on the wiring. I have the great wiring diagrams from Paul Bennett, Wiring Diagrams 308 365 400i 512 which is what leads to my question. I verified via my owners manual any differences between Paul's diagrams and my manual on the wire colors. Just a few different. However, what I have is a color difference in a few of the wires going to the bottom right block versus the owner's manual for a 1976. There is also one difference on the top of the block as well. I've attached a photo of the wiring on the bottom block and I've got a difference at positions 5/6/7.

    At position 5 instead of a green wire and white wire I have a single green wire.
    At position 6 instead of pink and red/black I have a white wire and a yellow/black wire.
    At position 7 instead of azure/black stripe and yellow/green stripe I have a white/red stripe and yellow/green stripe.
    On the top at position 4, both diagrams show a yellow/black stripe. My block is off by one position on this one and the single yellow wire should be at position 3, still though, no yellow/black wire is present to even go on position 4.

    So first, should I be concerned about this or is it possible that at the factory they just used whatever? Or could this be from some restoration of a previous owner. The left side matched up as expected.

    This car has an unknown past and I have yet to unravel it's tales. Crazy electronics is one thing I'm hoping to solve with Birdman's fuseboxes and rather than just numbering and reconnecting, I decided to try and verify everything was where it should be located, short of tracing wires.

    If anyone has photos of their 76 or can verify similar wire differences from their owner's manual, it'd be great to know.

    Thanks for any help!
    Russell
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  2. sltillim

    sltillim Formula 3
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    Nov 22, 2009
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    San Diego
    #2 sltillim, Aug 24, 2013
    I went through this. There are discrepancies between the two different documents. Go with the current set up. Mark every connection with magic marker either directly on each connector or Wrap tape and then mark them. Make sure you keep everything how it currently is.
     
  3. Jonny Law

    Jonny Law F1 Rookie
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    #3 Jonny Law, Aug 24, 2013
    I found just moving one wire over at a time from old to new worked for me. What didn't work was assuming the fuses would be grouped together by amperage.

    Case in point on a '81:
    - The far left fuse on the left bank is the fuel pump, its a 15
    - The wire core in the new glass fuses can be hard to see in sunlight.
    - Italian girls don't like being stranded on the side of the road waiting on a tow truck...in the rain...because of a blown 7.5 amp fuse.
     
  4. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #4 Steve Magnusson, Aug 24, 2013
    Last edited: Aug 24, 2013
    I believe that the GN (yellow-black) wire on the top at position 4 on the RH fuseblock is only used on the euro 308GT4 (not the early US/NA version 308GT4) -- sounds like you have the wrong OM and the wrong Paul diagram for your version 1976 308GT4.

    The US/NA OM for your model/year is 100/74

    The euro OM for your model/year is 91/74

    Which OM do you have?

    The good news is that the busbar connections of the top of the fuseblocks is the same for euro vs US/NA on your year/model, but I don't know if all the fuse values are the same (that's your homework ;)).
     
  5. vidkidruss

    vidkidruss Rookie

    Jul 13, 2013
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    Russell Harris
    #5 vidkidruss, Aug 24, 2013
    Ok, that might be it. I have an OM with cat # 124/76 . And looking closer at the manual, I see that the images are all Euro style. Paul only has one GT4 diagram and it's a 1974 but not sure if it indicates Euro or US.
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #6 Steve Magnusson, Aug 24, 2013
    If it doesn't say "North American Version" somewhere on the cover or title page, it is euro (standard) version OM. It's not a complete OM, but you can download a copy of the 126/76 OM Addendum (with wiring diagram) for 1976 NA 308GT4 from All Ferraris and see if that wiring diagram matches your car better.
     
  7. vidkidruss

    vidkidruss Rookie

    Jul 13, 2013
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    #7 vidkidruss, Aug 24, 2013
    All Ferraris did the trick! They had a 1976 NA version OM with wiring diagrams that verified my color wires for top and bottom. Mystery solved!
    Thanks Steve!
     
  8. vidkidruss

    vidkidruss Rookie

    Jul 13, 2013
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    Russell Harris
    #8 vidkidruss, Aug 24, 2013
    And I just found that Paul's site also had the NA and US versions as well, doh! Just didn't know where to look.
    R
     
  9. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    Jan 11, 2001
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    #9 Steve Magnusson, Aug 24, 2013
    Glad that you got it figured out, but you should disassociate that 124/76 OM from the car and get a copy of the 100/74 OM + 126/76 OM Addendum!
     
  10. Nielsk

    Nielsk Karting

    Dec 8, 2012
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    Central Florida
    #10 Nielsk, Aug 24, 2013
    From what I see in your picture it is a good thing you are doing this! You should replace all suspect / corroded spade connectors on the wires while you are at it.
     

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