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Installation Instructions for the Universal
Thermostatically Controlled Electric Fan Relay Kit

Be sure to route wires in a manner so that they do not chafe on any sharp metal edges and use proper terminals and connectors at all connecting points to insure proper electric fan function. These instructions can be used with single fan or multiple radiator fan relay kits as long and the combined current draw does not exceed 30 amps. See our radiator fan wiring diagram below. Contact us if you have any questions about installing a cooling fan relay.
  1. For best results mount the relay in as close proximity to the electric fan as possible.
  2. Install the thermoswitch into the cylinder head or intake manifold fitting as available per your application. Route the GREY 18 gauge wire and cut to proper length. Crimp the ¼” spade connector terminal on to the GREY wire and attach to the terminal on the thermoswitch.
  3. Route and connect the PURPLE 12-gauge wire to the printed to the positive (+) wire extending from the electric fan motor. If you want to change direction of air reverse this connection.
  4. Mount the circuit breaker near the power source you are using to power the fans
  5. Cut the RED 10 gauge wire so that it terminates near the circuit breaker, connect to one side of the circuit breaker using one of the supplied ring terminals. Attach another terminal on the remaining RED wire and connect to the other side of the circuit breaker. The circuit breaker will “pop” if the system is overloaded and will automatically reset once it has cooled down.
  6. Route the YELLOW 18 gauge wire to the ignition switch or an auxiliary “fan switch” if you are independently switching the fan system.
Relay Kit instructions