Do you guys have a guide on how to wire up a single electric fan to a switch in the cabin so that i can turn it on at will? I know they make a special harness that you can use but i wanted to go cheap here. to many expensises right now with my switch over from tbi to carb!

 

Why don't you just rely on the cool fan switch to operate the fan. But if you really want to do it, wiring is simple. You will need a switch, two wires. Run one wire from a constant power source such as the fuse box or battery to one prong on the switch. Splice the other wire into the power wire going to the fan motor and run the other side of that wire to the second prong on the switch. That's it! Power will be running to the switch all the time and when you want to turn on your fan, flip the switch (which closes the contacts inside the switch) and it routes the power from your source directly to the fan to turn it on. The ground on the fan plug must be grounded though in order for it to work. Just be sure to use some good gauge wire cause that is a lot of current being pulled through the wires to operate the fan.

 

In most of the aftermarket fans the switches are in the ground leg of the circuit. For instance there is a temperature sensor that completes the circuit to ground when the sensor reaches the "turn on" temperature and the fan comes on.

If you can determine which wire on the fan is the ground and splice another wire into this ground wire you can run this additional ground wire into the cabin, through a switch, and then to ground in the cabin. Turning this switch to ON will allow the circuit to complete to ground and run the fan. But you will need to determine if there is always power to the fan and it is activated by grounding.

John

 

If you are using the factory fan, then the fan motor is only waiting for the relay to close in order to route the 12vdc power to the fan motor. Again just look at my first reply to run a self application switch. The actual fan motor is grounded all the time but it just doesn't have power running to it. Thats why you must route a power wire. All you are doing when you do this is bypassing the relay.