Cooling Fan Problems

[EDT]

I thought I had the wiring done, but when I ran the car for the first time today, the cooling fan never came on. It was definitely hot enough and the fan does work. I'm using the RF wiring harness, and I've traced all the wires, and they seem to be right. The relay works. Where do I go from here? I'm pulling my hair out over this one.

[twan374]

Not familiar with the RF harness but if it uses the small 30amp relay thats built into the panel forget it . It will keep blowing the fuse and cook the relay. That being said it should be pretty easy to locate the problem. most set ups use a ground to trigger the relay That should be in the intake manifold some where hooked up to a sensor which grounds out when it reaches temp. You should be able to jump the lead to ground and the fan should come on. Also check the fuse. You can then locate the relay and remove it . The relay should have a little diagram on it. Jump the socket between the terminals for the power and the load with the motor at temp. The fan should go on. You can also use a test light to make sure you are getting juice to the hot side of the relay. I had an ez wire harness with a built in relay and had problems from day one. The FFR fan draws a lot of current and I wound up using a free standing 40 amp relay and never had a problem after that. sometimes the sensor will not ground out if you use teflon tape on it also.

[Fox2]

I too have the RF wiring harness. Ground the Dark Green Fan Thermo Switch wire. I am running a manual fan right now in the go kart stage through a toggle switch but the Dark Green Fan Thermo Switch wire is what grounds it with either the auto. or manual. My RF instruction book is Revision H Jan. 2011 you will see the wire on page 15. In the harness it was next to the Tan - Electric Choke wire. Let me know if it works for you. Rick at FFR tech. helped me with this one. He a good guy to know.

[EDT]

Thanks for the quick replies. I found the problem. A wire in my fuse panel had come loose. I hooked it back up, grounded the green wire and the fan now works.