APEXi Power FC E-Fan Relay Installation

Installation of the E-Fan Relay allows the PFC to turn on an aftermarket electric fan at a programmable water temp

Pic #1 (Relay)
Pic #2 (Connections)
Pic #3 (S5 Fan Trigger)
Pic #4 (S4 Fan Trigger)


Now that you have installed the Power FC, it is time to start taking advantage of some of its capabilities. If you have installed an aftermarket electric fan, that did not come with a thermostatic control, the PFC can be programmed to turn it ON and OFF at any desired preset temperature. First, we need to wire in a relay.

We opted to use a factory FC3s relay and connector for a few reasons; 1) We had lots of them available, 2) They are more robust then the ones available at the parts store, and 3) We wanted the install to look like it was supposed to be there. This is how we did itů

Tools Required:

Parts Required:


1. Our Banzai Racing PFC Harness Adapter is configured so that it can be used in conjunction with a relay to activate the Power FC to turn on an electric fan at a programmable water temperature; this is the Fan Relay Trigger, which previously functioned as the (GREEN single pin) diagnostic connector, located behind the driver-side headlight (Pic #3). [On the S4 models this is the ORANGE wire on the GREEN 2-pin connector (Pic #4)].

2. Run the required wires to the connector using the Relay Connection Diagram. The diagram shows the connector face; the wires exit the back.

a) Run the 12V constant wire directly to one of the 30 amp fuses in the fuse box or directly to the battery with an inline 30 amp fuse installed.
b) You can tap into one of the other relays for the 12V Ignition connection.

3. Consult the E-Fan manufacturer's wiring specifications to determine the positive lead required for your desired direction; pushing or pulling.

a) If mounted on the engine-side of the radiator, it needs to be pulling.
b) Connect Fan ground wire to chassis.

4. Access the PFC with a Datalogit. Go to tab 'Settings 3'. You will see 'Fan vs Water Temp'.

a) Change 'Fan # 2' to desired temperature. NOTE: Changes to Fan #1 will have no effect.
b) Start with a very low setting (35° Celsius e.g.) to verify that the fan is turning on. If everything works, then you can set it at your desired temperature.
c) We have ours set at 87° Celsius (approx. 190° Fahrenheit) which allows the thermostat to fully open.

FC3s Relay Connector Diagram

If you do not have a factory relay available, you can use a Standard 12V 30 amp Relay from your local parts store. Follow the above procedure using the wiring diagram below.

Pic #4 (Standard 12V 30 amp Relay)
Standard Relay Wiring Diagram

Click on images for larger view

Banzai Racing Inc. & associates are not responsible for any adverse effects arising from application of this procedure.

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