Mishimoto Radiator Fan Issues

Discussion in 'SN95 4.6L Mustang Tech' started by JBirdBLKVert, Sep 5, 2013.


  1. JBirdBLKVert

    JBirdBLKVert New Member

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    have a mishimoto radiator fan installed in my car. It is wired to my low side because its a single speed fan. After charging a/c I ran it and it overheated. So I figured to not run a/c. I then had headers changed and it ran fine till at an idle then fan wouldnt run and it overheated again. I then sct tuned it and now the fan comes on for a couple seconds and shuts off. Im wondering if there is something I can do to allow me to run the ac or why its not running normal with no ac on. Im really at my wits end and need some advice
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  2. JymboSlice

    JymboSlice Member

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    switch back to your stock fan
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  3. wmburns

    wmburns SN Certified Technician

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    The GT has a two speed fan control. When the CCRM changes from low speed to high speed, the power actually switches to a different wire. So it would be expected to see a single speed fan connected to only one leg to shut off when the CCRM changes speed.

    There are several ways to fix this depending upon your set up.

    Do you have a single fan or dual fans?

    Do you want the fans to change speed or change the number of fans running?

    This will require some electrical modifications. Having a set of wiring diagrams will be a big help. If interested in getting yourself a set I maybe able to help. PM if interested.

    OBTW, I have helped others previously on this very same question.
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  4. JBirdBLKVert

    JBirdBLKVert New Member

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    Its a single fan single speed. I want it to stay running when it turns on and I want to make it 2 speeds
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  5. wmburns

    wmburns SN Certified Technician

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    Insert a ballast resister in the low speed line. Some experimentation will be needed to determine the correct value. As an option consider using the ballast resister from a late model (03+) stock Mustang fan.

    Tie the high speed and low speed lines together to power the new fan.

    On some application a diode is needed between the HS and LS line. Recommend doing this only if needed.

    The ballast resister will lower the voltage during low speed operation. The fan should run slower. During HS operation, the fan will get the full voltage and run at max speed.
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  6. Mishimoto

    Mishimoto Member

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    This is some great information wmburns! Thanks a lot for helping out in this situation. :nice:

    Hopefully the OP has figured it out and is no longer having issues?
    #6

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