An automotive fan plays a critical role in an automobile's cooling system. The fan moves air through the radiator, which allows the engine coolant to lose heat more quickly. Unfortunately, an automotive fan is a high-current electrical device. Directly connecting the fan's electrical leads to a switch inside the automobile can cause an electrical fire. To switch an automotive fan on or off safely, you must wire it to a relay. A relay is an electromechanical device you can actuate using a low-power switched circuit. When actuated, the relay can act as a remote switch for a high-power device, thus minimizing electrical hazards.
Instructions
- 1
Use the electrical pliers to cut six pieces of electrical wire. Strip 1/2 inch of insulating material from the ends of each wire piece.
2Place the first splice terminal connector over the automobile starter wire and check to ensure that the starter wire is completely at the bottom of the splice connector gap. Insert one end of the first piece of electrical wire into the hole on the side of the splice connector, and crimp the connector firmly to create the electrical joint.
3Use the soldering iron to solder the unoccupied end of the first piece of wire to one of the terminals on the rocker switch. Solder one end of the second piece of wire to the remaining terminal on the rocker switch.
4Solder the free end of the second piece of wire to the "85" terminal on the relay. Solder one end of the third piece of wire to the "86" terminal on the relay.
5Place the first ring terminal over the unoccupied end of the third piece of wire and crimp the terminal to the wire. Using the adjustable wrench, loosen the retaining nut on the negative battery terminal connector. Place the ring terminal over the retaining bolt and replace the retaining nut. Tighten the nut so it holds the ring terminal snugly to the terminal.
6Place the second ring terminal over one end of the fourth piece of wire and crimp the terminal to the wire piece. Loosen the retaining nut on the positive battery terminal connector. Place the ring terminal over the retaining bolt and replace the retaining nut. Tighten the nut so it holds the ring terminal snugly to the terminal. Solder the unoccupied end of the fourth piece of wire to the "30" terminal on the relay.
7Solder one end of the fifth piece of wire to the positive terminal on the fan. Solder the other end of the fifth piece of wire to the "87" terminal on the relay.
8Solder one end of the sixth piece of wire to the negative terminal on the fan. Place the second splice terminal connector over the third piece of wire, and check to ensure that the third piece of wire is completely at the bottom of the splice connector gap. Insert the free end of the sixth piece of wire into the hole on the side of the splice connector, and crimp the connector firmly to create the electrical joint.
