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High Performance Cooling Fans Control Relay & Harness With Thermal Switch

Included Parts: Relay & Harness, 185 Degree Thermal Switch, Fuse Holder, Fan Pigtail Harness, Fuse, Terminals

These instructions will show you how to properly install the relay and harness for our Performance Cooling Fans. Our Fan Relay Kit can be directly installed on any vehicle with simple connections.

Instructions:
The relay should be mounted in a secure location away from extreme heat or outside elements. Connections to the vehicle should be done per the notes and diagrams. For low profile fans, a 15 amp fuse should be used; for medium profile fans, a 20 amp fuse should be used. For dual fans exceeding 30 amps, a second relay is recommended.

click here for a .pdf copy of the below instructions

Fan Pigtail Connections

Red: Connect to Red harness wire using supplied yellow wire connectors.
Black: Connect to ground using attached ring terminal.


Single Fan Connections

Single Fan Connections

Red: Connect directly to the red wire on the fan pigtail harness (included).
Yellow: Connect directly to fuse holder (included).
Orange: Connect to a+ 12v ignition source when key is in the run position. Can be connected directly to a+ 12v source for continuous fan operation regardless of ignition switch (not recommended).
Grey: Connect directly to Thermal Switch (sending unit) using supplied blue ring terminal.
Fuse: Connect inline to Yellow wire and as close as possible to Battery, as shown.


Dual Fan Connections

Single Relay Dual Fan

Red: Connect directly to the red wire on both fan pigtail harnesses (included).
Yellow: Connect directly to fuse holder (included).
Orange: Connect to a+ 12v ignition source when key is in the run position. Can be connected directly to a+ 12v source for continuous fan operation regardless of ignition switch (not recommended).
Gray: Connect directly to Thermal Switch (sending unit) using supplied blue ring terminal.
Fuse: Connect inline to Yellow wire and as close as possible to Battery, as shown.


Thermal Switch Installation:

The Thermal Switch is an OE-style, thermostatically controlled sender that switches the fans on at 185 degrees when wired properly. When the temperature drops to 165 degrees, the switch opens and the fan(s) will switch off. The sender has a 3/8" NPT thread and can be mounted directly into a water port on the cylinder head or the intake manifold. An adapter is included for applications with a ½" NPT port, other sizes can be found at most automotive parts stores. It is important to not use Teflon tape or other types of sealant on the threads as it could create a poor electrical connection that would cause incorrect temperature readings and improper fan operation.


Troubleshooting

If you experience overheating, there are a number of reasons that can cause this. The first step in the process is to determine where the problem is, and to narrow it down to a specific location. Please contact our technical advisors at 951/245-9464 if you cannot determine the cause using our chart below.

Problem Cause Solution
Engine overheats at low speeds or at idle Poor air flow through the radiator Install electric fan, be sure air flow is not restricted through radiator
Poor ventilation in engine compartment Make sure hot air can escape the engine compartment
Radiator is insufficient or plugged up Install electric fan, be sure air flow is not restricted through radiator
Engine timing is too far advanced Adjust timing to proper specs
Carburetor idle circuit is too lean Adjust idle circuit
Engine overheats regularly Thermostat failure Replace thermostat