1986 Mondial - fusebox question | FerrariChat

1986 Mondial - fusebox question

Discussion in 'Technical Q&A' started by teambft, Dec 27, 2013.

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  1. teambft

    teambft Rookie

    Nov 28, 2013
    26
    Brentwood, TN
    #1 teambft, Dec 27, 2013
    Last edited by a moderator: Sep 7, 2017
    I'm following the below post from a while back in an attempt to rewire/bypass my fuel pump relay. The thread states to "tap off the large red power input wire going to the fuse panel".

    Standing from the rear of car looking forward, the fuse box has two very heavy gauge red wires on the left that each plug into the black fuse box. Would I tap into these in photo #1?

    Or would I tap into one of the two red wires on the right side of the box in photo #2? Thanks for any advice.

    Rewire post:
    As many of you know, the fuel pump circuit is lousy on the '80's cars. Often you will find that the fault lies near the fuse panel or relay. Here is how I fixed the 86 Mondial 3.2 panel. The terminals on the relay are marked 30(power +12 in), 85(relay energize), 86(relay energize), 87(relay +12 output), and in the case of the Mondial fuel pump relay it has 2 87 terminals. So- to make the best bypass systyem for the poor fuse panel...
    tap off the large red power input wire going to the fuse panel with an inline fuse holder and crimp a female 1/4" terminal on the end you are going to attach to the 30 relay terminal. make 2 extension wires to supply trigger power to the relay, a 1/4" male on one end, a 1/4" female on the other. Plug these into the corresponding spot where the fuel pump relay came from and plug them into the 85 and 86 terminals on the relay.
    cut the 2 brown wires from the 4th terminal from the bottom right connector and attach a female 1/4" connector to each and install them on the 87 terminals of the relay. Thats all, full bypass of the fault prone relay/fuse board.
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  2. blownfuse

    blownfuse Karting

    Jul 16, 2012
    104
    Campbell, California
    The two large wires on the left (Photo #1 in your post) are the ones that feed power to the board. You can tap either one of them, but be careful that your connection is tight. A loose connection here can lead to fried wires. :(
     
  3. teambft

    teambft Rookie

    Nov 28, 2013
    26
    Brentwood, TN
    Thanks a ton!!! Just ordered a new box from GT Car Parts - as you all know, Bill is a great guy....very helpful and will have it Thursday.
     
  4. Mr. V

    Mr. V Formula 3

    Oct 23, 2004
    1,247
    Portland, Oregon

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