1996-2004 Mustang Manual High Speed Fan Switch

       This article covers how to wire your factory fan so that you can manually turn it on either while the car is running or with the key turned to the on position. What this mod does is grounds out the high speed fan so you can cool down the engine. Along with cycling the coolant it's a great way to cool your car down at the track. I first did this based on an article by Scott96Cobra on the Corral.        

       Remove the passenger threshold plate and side kick panel then find the bundle of wires coming from the PCM. Within that bundle of wires find the light green wire with violet stripe (see figure 1). Using wire cutters carefully cut the outer wire insulation exposing the wire, do not cut the wire (see figure 2). Take the piece of 16 gauge wire and trim the insulation so the wire is exposed and use the wire splitter and splice it into the exposed light green/violet wire (see figure 3). 

        Next route the wire up underneath the dash and zip tie along the way keeping it away anything that can move hit it. Route the wire to the center console and back to the location where you will mount your switch. In this install I used an on/off rocker switch I purchased online and used a dremel to cut out the factory coin holder so I could mount it in a stock location (see figure 4, 5). Another option that could give a more stock look would be to use a factory fog light switch. The fog light/coin holder location is different through the years but any of the locations can be used.  

        Cut the length of wire so it ends in the location of the fan switch. Cut the insulation and crimp a female terminal connector for the switch. Take the remaining length of wire and cut the insulation and crimp another terminal connector for the other terminal of the switch. Run that wire back to the center console area. On the passenger side pull the carpet back from the center console area. I used the green bolt as a grounding location for the switch. Cut the wire to length and install a ring terminal. Remove the 7mm bolt and install the end of the wire (see figure 6). 

       Push the carpet back into place, reinstall passenger side kick panel and threshold plate. Test the switch with key turned into the on position without turning the car on and you will hear the fan kick on (see figure 7 switch off, figure 8 switch on).

        For any questions regarding this tech article please visit our forums at www.modularrevolution.com/forums/forums.php

Written by: Bill Putnam

Product Manufacturer: NA

Difficulty Level:

Time: 30 Minutes

Tools: Wire cutters, Dremel, 1/4 drive ratchet, 7mm socket.

Parts: 6 feet of 16 gauge wire, zip ties, wire splitter, two female wire terminals, ring terminal, on/off switch or factory fog light switch. 

Pictures

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