How to Wire a Radiator Fan

What You'll Need
Drill machine

Before understanding how to wire a radiator fan, it is important to understand the role that a radiator fan plays in a car. The car basically moves forward due to a mixture of air and fuel that is ignited by compressing and expanding the mix inside the cylinders. This generates a heat which in turn can cause damage to the engine. This is where the radiator comes into play and its job is to remove the heat from the engine. The radiator is a large matrix of small pipes. It cools down when the coolant passes through it removing the heat that has accumulated in the engine. When the coolant reaches a temperature of 100 degrees Celsius, the computer in the car will turn the radiator fan on to further cool down the coolant. This helps in moving the heat from the engine to the radiator fins. As the air is moving at very high speeds over the radiator, this will cool down the liquid and the hydraulic pump will pump the coolant back in the engine.

If minor radiator leakages occur, the wiring of the radiator should be checked. It may also be required when the fan is an addition to or a replacement for the existing fan.

Step 1: Connections

Unscrew the nut on the negative side of the battery and disconnect the cable. The fan controller needs to be installed by drilling a hole for its mounting. This should be placed as close to the battery as possible and should be a maximum of 10 inches from the radiator.

The in-line fuse open-end connector should be connected to the positive battery terminal.

Wires need to be connected to both ends of the in-line fuse.

Step 2: Wiring

Cut a wire, strip the insulation from both the ends and attach to the fan controller. The other end of the wire that was fitted to the in-line fuse needs to be fitted with the female blade terminal.

Step 3: Terminals

The female blade terminal needs to be pushed onto the fan controller marked B+. The black wire that comes attached to the fan controller needs to be attached to a good ground. The female blade terminal needs to be attached to the red wire on the fan. This terminal needs to be pushed on to the remaining terminal on the fan controller. An open terminal needs to be attached to the black wire on the fan and ground to the frame.

Step 4: Temperature Bulb

The temperature bulb and line need to be unraveled from the fan controller. The temperature bulb needs to be inserted into the engine side of the radiator.

Step 5: Reconnection

The negative battery cable needs to be reconnected.

Now, you can start the engine and observe the temperature gauge to see that it is operating at normal temperature levels.